To simplify things, I'll put it as if it were my father:

My mother conceived me without being married, and my father never acknowledged me. I don't remember ever having met my father.

What is this kind of "biological-only" father called?

  • Just to clarify, do you want a word that specifically means a biological father who absconded? If yes, then you'll have to use adjectives.
    – vickyace
    Commented May 5, 2016 at 12:05
  • 57
    Using the term biological father instead of simply father implies a situation like this.
    – z7sg Ѫ
    Commented May 5, 2016 at 12:39
  • @vickyace yes, although a broader term including this case would be acceptable. Commented May 5, 2016 at 12:41
  • 3
    the simple answer to your question is there are many varieties of meaning here. note that indeed I do not understand your description. Did you mean your mother eschewed men, chose a man to use as a father (perhaps the man did not even know)? Or, do you mean the man "ran off" (perhaps after promising marriage) -- or what? They are all totally different.
    – Fattie
    Commented May 5, 2016 at 22:19
  • 1
    @Joe Blow: Or the mother doesn't know for sure which particular man was the father, or does know but never told him, or maybe never saw him again after that one exciting night...
    – jamesqf
    Commented May 6, 2016 at 2:38

16 Answers 16


I'm not sure why no one has said it, but the best answer is right in your question:

I may have inherited a heart condition from my biological father.

I have a situation similar to the one you describe, and my whole life this phrase has never failed to convey the meaning of the genetic-only relationship.

  • 3
    Someone is probably going to refer to dictionaries and say biological father does not preclude an active, genetic parent. However, I reiterate in the decades I have used this term to specify a parent that OP describes, I have never had someone misunderstand the meaning. Commented May 5, 2016 at 15:26
  • 11
    +1 - In practice, no one ever says "biological father" for someone in an actual active parenting role. The only caveat is that it most typically serves to differentiate between a (absentee) genetic parent and a (present) adoptive one. youtube.com/watch?v=6kyDKBpq2g4 Commented May 5, 2016 at 16:22
  • 6
    @ChrisSunami: "no one ever" is perhaps a bit too strong. I see no problem with something like, "Out of her entire group of friends, she was the only one being raised by both her biological parents." But yes, there's generally no need to describe someone as a "biological father" if he's also the unqualified "father".
    – ruakh
    Commented May 5, 2016 at 19:43
  • 4
    For brevity and informality, the slang term "bio-dad" is becoming more common as an abbreviation for biological father.
    – recognizer
    Commented May 5, 2016 at 21:55
  • note however that "biological father" may be either positive or negative or indeed neutral. indeed, it's totally common to use it (for one reason or another) in situations where the parents are indeed still married. there is no one answer to this question as there are too many variations.
    – Fattie
    Commented May 5, 2016 at 22:20

If you're looking to emphasize his lack of involvement, a common description for a father-by-biology-only is: "sperm-donor". (US)

Note that this term is often used outside the context of a formal sperm donation arrangement, usually pejoratively, emphasising that biological father did not provide a parenting role.

  • 4
    +1 but I think the hyphen unnecessary: spell open. Commented May 5, 2016 at 12:45
  • 27
    This term implies that there was no relation between parents, which is not my case. Commented May 5, 2016 at 12:47
  • 38
    This is often used somewhat sarcastically to mean "the only involvement the man has had in my life was providing half of my genetic material" and doesn't necessarily speak to the relationship between the biological parents prior to the birth.
    – Sabre
    Commented May 5, 2016 at 13:18
  • 7
    @Sabre What do you mean "often used"? I have never heard of this outside of its literal meaning.
    – Jordan.J.D
    Commented May 5, 2016 at 18:23
  • 14
    @Jordan.J.D - (AmE here) I've heard (in conversation) "sperm donor" when the person was talking not only about absent father but also a detested father. I've actually heard it often. It shocked me the first time, it seemed so hostile (it was about a detested father), but it's fairly common now. I've even seem it used in media this way. Commented May 5, 2016 at 18:51

Try birth father also called a biological parent. It means a biological mother (birth mother) or biological father(birth father).

Here is a definition from another site. This site defines it as the man who was someone’s father when they were born rather than the man who has adopted them. It is closer in meaning to what the op asked.

  • 1
    I think parent has more implication than biological only. Biological only, imo, tends to be DNA donor. Parent is about provision and nurture. Commented May 5, 2016 at 18:19
  • @Mari-LouA I think I didn't give a definition in the answer because I thought it was not needed given how easy it is to figure out the meaning from the word itself. But point talen.
    – vickyace
    Commented May 6, 2016 at 10:30
  • What if your father died before you were born? My father's father died before my parents were married, so I say that I do not have a paternal grandfather. So many possibilities. I liked your Comment to the Question.
    – user126158
    Commented May 6, 2016 at 14:45

I've heard "absent father" used in this situation.

In fact, parental absence or absenteeism is recognised in psychology.

  • 1
    This phrase is similar enogh to "absent friends", that if I heard it I'd assume the father in question is dead.
    – T.E.D.
    Commented May 6, 2016 at 13:35
  • 3
    I think "absentee father" is more accurate and certainly something I have heard used in British English. Commented May 6, 2016 at 16:15
  • @LaconicDroid - That I've heard. It implies the guy is supposed to be there though. Often used when the parents are nominally together, but the father doesn't spend much time with the kids (usually due to work, but sometimes due to other social commitments).
    – T.E.D.
    Commented May 6, 2016 at 18:45
  • 1
    To me this suggests that the father left (or died) after the child was born, but still too young to remember him. "Biological father", on the other hand, implies a father who left (or died) while the mother was still pregnant, who thus possibly never even saw his child. Commented May 6, 2016 at 21:47
  • "Biological father" means nothing than the biological fact. It says nothing about the relationship. I'm quite sure the man who was married to my mother and raised me for many years was my biological father.
    – gnasher729
    Commented May 8, 2016 at 22:03

I'd say that all that he is, is progenitor.

A person or thing from which a person, animal, or plant is descended or originates; an ancestor or parent:
'his children were the progenitors of many of Scotland’s noble families'

In my mind that properly defines both the role in siring and the lack of any involvement afterwards.


  • It doesn't imply any responsibility at all. Perfect for a runner.
    – vickyace
    Commented May 5, 2016 at 12:23
  • 8
    The problem with this term is that it applies to any ancestor, not just parents. Commented May 5, 2016 at 12:29
  • @Walter Tross, quite right. But alternatives like sire suggest respect, and a term like begetter suggests the intention to generate offspring. Your story seems to imply the absence of any such factors. Just my 2 cents though.
    – Bookeater
    Commented May 5, 2016 at 12:41
  • 1
    @Bookeater, where are you getting from 'Progenitor' that it defines a lack of involvement? My take is that in stressing an ancestral role it says nothing about the progenitors relationship with his immediate progeny and any other remoteness is a consequence of temporal separation, surely?
    – Spagirl
    Commented May 5, 2016 at 15:09
  • "Progenitor" does not imply a particular gender, and also could be used for someone further up the family tree (grandfather, great-grandfather, etc.) So I don't think its specific enough for this case.
    – T.E.D.
    Commented May 6, 2016 at 18:48

You can try:

genetic father

Which suggests that it is only your father in terms of genetic material... kind of like the sarcastic use of "sperm donor" but without other potential misleading connotations.

Or if you like sarcasm and relying on the audience inferring the meaning:

invisible father

  • 3
    I would assume invisible father to mean someone who spends all his time at work and/or in a bar.
    – pipe
    Commented May 6, 2016 at 0:50
  • @pipe: I would agree that that's probably the common implied meaning. It's hard to accurately convey something sarcastically in general. =)
    – user21820
    Commented May 6, 2016 at 1:01

Unfortunately, the term Baby Daddy seems to be the term most used in common practice today. This seems to have started with descriptions of celebrities and their children in the tabloids. This term has deplorably now entered the common nomenclature.

Baby Daddy - slang: the biological father of a woman's child; especially : one who is not married to or in a long-term, intimate relationship with the child's mother http://www.merriam-webster.com/dictionary/baby%20daddy

  • 8
    While “baby daddy” nails the relationship between the biological father and the mother, no relationship with the mother doesn't always mean no relationship with the child, so I'm not sure this quite fits.
    – Morgen
    Commented May 5, 2016 at 21:52

I guess you could describe them as your estranged biological father

to cause someone to be no longer friendly or close to another person or group


  • 12
    Doesn't estranged imply that there has been a time when he was not a stranger to me? Commented May 5, 2016 at 12:46
  • maybe .... the male in question must have been close to the mother at some point. they broke up, and now he is estranged ("from the mother" or "from the family" if you will). tricky one!
    – Fattie
    Commented May 5, 2016 at 22:27
  • @JoeBlow - you should get acquainted with the concept of "one night stand". Commented May 8, 2016 at 17:14
  • In which case the person is not an "estranged father".
    – gnasher729
    Commented May 8, 2016 at 22:00
  • Hi @BobJarvis. That is a commonplace phrase. Were you being sarcastic / witty?
    – Fattie
    Commented May 9, 2016 at 1:16

If you're able to change the usage a bit, I'd offer sire. Changing the usage to something more like:

Having been more sired than fathered, I never knew the man.

helps to differentiate between that alternate meaning of sire, which is a title of respect and nobility.


There are several terms, the best one to use depends on nuance. To express the connotation of a parent who should have been there but wasn't, use the (mildly) pejorative term absentee father.

absentee: a person who is expected or required to be present at a place or event but is not. Google

  • I believe this is the best answer here. "There are several terms, the best one to use depends on nuance." Precisely. (And to repeat, it's actually not clear precisely which variety the OP means.)
    – Fattie
    Commented May 5, 2016 at 22:29
  • @JoeBlow - Disagree. This term implies the person is supposed to be there, but isn't. I've typically seen it used for fathers in supposed traditional nuclear families who don't spend much time at home with the kids.
    – T.E.D.
    Commented May 6, 2016 at 18:51
  • Hi TED, I'm not sure how much clearer Chirs' description could be: here, I'll quote it verbatim: "To express the connotation of a parent who should have been there but wasn't, use the (mildly) pejorative term absentee father."
    – Fattie
    Commented May 7, 2016 at 2:57

So many names for this chap. Here's another one: genitor.

The word comes up every now and then in Countdown, a letters and numbers quiz in UK, that's how I know it.

  • "2. Cultural Anthropol. A biological father as opposed to a man who assumes legal and social responsibility for a child not his own. Opposed to pater n.2 2b." (OED Online)
    – JEL
    Commented May 6, 2016 at 23:17

I have heard this used: Bio-dad.

It is often used as pejorative, though much less powerfully than "sperm donar".

Most often used to refer to a biological father who is less involved than a step-father, or to a biological father who has little-to-no interaction with the child.


Many words have been used, but I don't think anyone mentioned that different terms are appropriate for different situations.

"Biological father", or more unusual "genetic father" just describes the biological situation without any judgement. It will even be used to describe the husband of the wife who raised the child in cases where people doubt it. "My husband is indeed the child's biological father".

"Sperm donor" in situations where a male was just used to produce a child, without intention on either side for that person to enter the role as a father.

An "absentee father" is a person who is supposed to be there as a father but isn't. An absentee father may be absent since before birth or left yesterday. "Estranged father" is a person who isn't there anymore. The "estranged" means he wasn't always absent.

"Deadbeat dad" is an insult for someone who doesn't meet his legal obligations.

"Baby daddy" is just ridiculous.

Seems nobody did think of situations where the biological father doesn't know he's the father, where the biological mother doesn't know he's the father, where the child is adopted and never meets any of their biological parents, or where the mother just finds a better father for her child.


I would choose begetter to descibe this situation. I am German and we use the word "Erzeuger" which normally simply means "producer" but in the sense of relationship begetter is more apropriate I guess. (and besides I really don't think it is so wrong to use a special term for this)

  • 1
    "Begetter", and the verb "to beget", aren't used in contemporary English, though they are still widely known (and appear in dictionaries) because of their use by Shakespeare and in the King James (1611) translation of the Bible.
    – alephzero
    Commented May 8, 2016 at 1:58

This may not be what you're looking for, but I thought it would at least be related to the question and interesting for a non-English speaker.

There are people that make a strong distinction between "Dad" and "Father".

This article was found using a Google search of "father vs dad", and it explains the difference that some people make:

A father is someone who believes that by donating his sperm for your creation, he has done his duty in life. A dad is someone who gets up every day and does whatever he can to put a roof over your head, clothes on your back and food on your table.

In my personal experience, this distinction tends to be made by people who have either a bad father or a bad step-father. Also, some people have the opposite associations of the words (father is loving, caring, dad was just the sperm-donor...). For instance, there is a song lyric from the popular 90's band Nirvana in which the singer wishes his father would have been more involved:

I tried hard to have a father. But instead I had a dad.

In this case, dad has a bad connotation.

The dictionary definitions of the two words don't match these perceived meanings, but when speaking with certain people, you might get corrected on your word choice.

  • 3
    As someone in that situation, that may be his own personal code, but its not universal. There are people who actually reverse his meaning on those words. For me I would never make the distinction that way to someone who didn't otherwise know my situation, because it doesn't actually clarify things. At least not without stopping to write an entire essay, like he did. Perhaps he hands people photocopies of his essay to read first before speaking whenever the topic comes up in conversation.
    – T.E.D.
    Commented May 5, 2016 at 16:43
  • 1
    @T.E.D., Yea, I'm not saying its an important distinction or even a correct one, but I have known a few people that would use one word but never use the other one because of their feelings. I thought if nothing else its good to know its a thing.
    – JPhi1618
    Commented May 5, 2016 at 17:18
  • 1
    I have never heard of anyone making such a distinction. Furthermore if someone were to make these personal definitions I could just as easily see them using the exact reverse (father just being a technical term for he who fathered you and dad being a term of endearment for a loving parent...in fact if anything that seems the more logical way to do it). I think the takeaway from this is that if you have to defend your answer's main point by declaring that it is neither important nor correct then it's probably not a good answer. Commented May 6, 2016 at 1:20
  • I admit it's probably not the answer the OP wants, but it does provide a useful detail to the word usage. It's not meant to be the answer, but it was more than a comment.
    – JPhi1618
    Commented May 6, 2016 at 1:23
  • 1
    -1, I waffled on downvoting this, since you explain why it's a poor answer right in the body, but eventually did anyway.
    – DCShannon
    Commented May 7, 2016 at 0:54

Your father is your father, the father you never knew. There is no special word for this all-too-common situation. Don't judge him too harshly until you hear his side of the story.

Birth father can't be right, since fathers don't give birth. Birth mother is redundant: mothers give birth, even if maybe some other generous, or merely put-upon, lady brings you up.

Words are tools, and using a tool the wrong way damages it. A new hammer you can always buy, a new language - not so easily.

  • Don't worry about judging too harshly. Besides, I made a mistake in my question: I wanted to write “as if I were my father”, because actually the guy is my grandfather. But I'll leave it like that for simplicity's sake. I must say I don't agree with what you say about birth parents. I think that birth here means something like “birth giving only”. Commented May 5, 2016 at 13:31
  • 3
    Places don't give birth either...yet we all have a birthplace. Neither do days...yet I notice myself having a birthday every year. Birth father simply implies the father figure associated with your birth birth (i.e. the one that gave the genetic material leading to it)...not that he actually birthed you. Nor is birth mother redundant, as there are many people with mother figures other than the woman that birthed them (ex: adopted children is a big one). Commented May 5, 2016 at 21:28
  • In my previous comment, I should have written “birth-related only” instead of “birth giving only”, which applies only to mothers. Commented May 5, 2016 at 22:13

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