Is there a word for "a name you legally gave yourself"?

Question

Let's say that there's a woman known since birth as Alice Smith who later changes her name to Mary Jones. 'Alice Smith' would be her "birthname"; is there a word for Mary Jones meaning "a name she gave herself"?

I see that there's a word "autonym," which would seem to be what I'm looking for, but it does not appear to actually have that meaning.

Note that I'm not looking for the term "married name," which would apply to a name acquired through marriage.

It could of course be the case that a person legally changes just their first name (not a nickname but a completely different name), but keeps the last name. What would that first name be called?

UPDATE: Lots of good answers here, getting at various nuances. In the particular case, I am asking about, the name was legally changed, so many of the answers (like "pseudonym") probably wouldn't work. Sorry I wasn't clearer when I said that she "changes her name."

Answer 1

If the person writes under a "false name" then pseudonym is the answer.

If the person has chosen to call him or herself with one name only, such as Adele, Prince, Pelé or Sting, then the term is mononym. For example, “Her mononym is Shakira.”

A single name by which a person, thing etc is known. For example, Madonna (the pop musical artist)

Talking of Prince, when he changed his name to the so-called ‘love’ symbol , for a number of years he was known as "The Artist Formerly Known as Prince", "TAFKAP", or just "The Artist". Likewise anyone could rename him or herself and say:

I'm [new first name], formerly known as [old first name].
OR
I'm [new first name], but I used to be called [old first name].

If a person dislikes their first name (for whatever reason), they can just call themselves with a different name. Sometimes a family nickname sticks, and that person grows up with that name. Changing a name by deed poll might include a lengthy process depending on one's nationality.

The most common use is a name change through a deed of change of name (often referred to simply as a deed poll). Deeds poll are used for this purpose in countries including the United Kingdom, Ireland, New Zealand, Hong Kong and Singapore. In the UK, a deed poll can also be used to change a child's name, as long as everyone with parental responsibility for the child consents to it and the child does not object to it. The child's parents execute the deed poll on the child's behalf. In some other jurisdictions, a person may simply start using a new name without any formal legal process.

Wikipedia

Oxford Dictionaries:

pseudonym
(noun)
a fictitious name, especially one used by an author.
"I wrote under the pseudonym of Evelyn Hervey"

synonyms: pen name, assumed name, alias, professional name, sobriquet, stage name, nickname

Answer 2

Alias is the name that you use in addition to your real name. It doesn't have a connotation of self-given, but it doesn't have a connotation of others-given, either.

an additional name that a person (such as a criminal) sometimes uses.

[Merriam-Webster]

"Self-given alias" will be much clearer in your context.

Answer 3

I'm going with "legally assumed name," because

• It does imply that the name has been changed.
• It does not imply that the name is not a true, legal name.
• It does not have an implied context, e.g. war, theater, authorship, or crime.

Thanks to Mazura for the hint, which led me to this in Wikipedia:

Most state courts have held that a legally assumed name (i.e., for a non-fraudulent purpose) is a legal name and usable as their true name, ...

although it does go on to add this:

... though assumed names are often not considered the person's technically true name.

Answer 4

Consider, moniker.

: a name, title or alias Computer Desktop Encyclopedia

He gave himself the moniker of Drew Danburry, hit the road with his guitar and never looked back Kuer

Everyone knew her as Nancy.

Dear Word Detective: I have often been puzzled by the derivation of the word "Monica" or "Moniker" when used in the context "Can you please stick your moniker on here," meaning "can you please sign this" or "can you please put your signature on here." In the past I have been told that it was possibly used in a kind of coded slang used by Irish Americans. But even if that were true, it still doesn't explain the derivation. I would have thought it much more likely to be cockney rhyming slang -- I'd love to bet there was a famous socialite called Monica Rignature or something ("Rignature - Signature"). Ha Ha! -- Adam Archer.

Well, that's not absolutely impossible, since a couple of the theories that are considered possible explanations for "moniker" (as it is usually spelled) are nearly as odd. That's a sort of backhanded way of admitting that no one knows exactly where "moniker," meaning "a name, especially an assumed one," or "a nickname," came from, but at least we have some entertaining possibilities to poke at.

"Moniker" first appeared as slang around 1851 in several different spellings, including "monaker," "monarch," "monekur," "monikey," "monnick," and "monniker." By the 20th century, the spelling "moniker" seems to have largely won out, although the variant "monica" is cited in the Oxford English Dictionary from 1968.

The pioneering etymologist Eric Partridge favored the notion that "moniker" is related to "monarch," in the sense of "king," in that one's name "partly rules" one's life. Frankly, this seems a bit of a stretch to me (and rather literary for what was, after all, originally street slang).

Another interesting theory explains "moniker" as originating in "back-slang" (a reverse slang common in Britain) for "ekename." "Ekename" was the original form of our modern word "nickname," "eke" being an old English word meaning "additional." (Through a process called "metanalysis," the "n" in "an" in the phrase "an ekename" drifted over and gave us "a nickname." The same process transformed "a napron" into "an apron.")

Anyway, the reverse slang for "ekename" would be "emaneke," which gradually mutated, according to this theory, to "moneker" and so on. Again, this is far from impossible, but seems a bit too elaborate.

Perhaps the simplest theory (and I like simple theories) is that "moniker" is just a blending, perhaps originally jocular, of "monogram" and "signature." The Word Detective

Answer 5

Their new title is the product of a name change, for which Wikipedia uses the word adopted a lot.

Informal methods of a name change include assumed names and common law names. Once all the paperwork clears, it will become their legal name which would then be different from their given name.

A person's first legal name generally is the name of the person that was given for the purpose of registration of the birth and which then appears on a birth certificate (see birth name), but may change subsequently.

_{This is an American's view point; we don't have 'deed polls'.}

---

Edit:

The OP favored assumed name for their purposes. E.g.:

They fled their oppressive life in the city, took an assumed name and began their life anew.

Answer 6

You might also consider nom-de-guerre

It may not technically be English, but it's used often, and has been more-or-less adopted, just like many other words of foreign origin.

(See this, from Wikipedia)

Answer 7

Nom de Jure-- French borrowed term, De Jure is used to form compound terms. It means 'based on or according to law' (Merriam-Webster.com) Examples include nom de Guerre (Patton: Óld Blood 'n Guts', Nom de Plume (Compte St. Charles Armand Gabriel de Gramont: Ted Morgan).

Answer 8

a self-given nickname or the name she gave herself would suffice.