So basically, I know the name for both sides of a coin, yet not the coin itself.

In other words, when you refer to a coin, you don't want to say 'this object with one side heads, and the other tails', you would want to say 'this coin'. What I want is a general term to refer to two ideas, that are the absolute opposite to each other. I can't really use the word 'concept', or 'idea', because such words are already assigned to the very concepts/ideas themselves.

  • Might as well close the whole site then. If you can find a commonly available reference, i'll be stunned. Commented Jun 19, 2016 at 23:47

14 Answers 14


polar opposites:

polar opposite ‎(plural polar opposites):

The complete opposite, opposite in every way.


"Polar opposites" might also refer to the scientific or technical definition of two things having exactly opposing or inverted polarity, sign, orientation, or some other property.

  • Oh yeeeah, hey I like that, partly because it's defined exactly as required, and also as it ties into the concept of polarity. Commented Jun 2, 2016 at 8:05
  • @user2901512 - Half the words on this page fit; "defined exactly as required". It has become a question of usage. I would not, personally, refer to the two sides of a coin as polar opposites (but they sure are). This is however, the most direct answer to the title. +1.
    – Mazura
    Commented Jun 3, 2016 at 21:51

I'd suggest dichotomy:

a difference between two opposite things : a division into two opposite groups.

Source - Merriam-Webster

  • 3
    I'm sorry but "dichotomy" represents the difference or division itself and not the two ideas.
    – vickyace
    Commented Jun 1, 2016 at 20:26
  • 1
    " What I want is a general term to refer to two ideas, that are the absolute opposite to each other."
    – Bob Stout
    Commented Jun 1, 2016 at 20:27
  • 7
    @BobStout There is a dichotomy between these two things that make them "two opposite things." They are not, collectively, a dichotomy.
    – vickyace
    Commented Jun 1, 2016 at 20:35
  • 3
    @vickyace, I have heard "dichotomy" used more often with the meaning "a pair of items which are complete opposites" than with the more technically exact meaning of "the distinction or difference itself (between two opposites)." I think the word is growing into this use.
    – Wildcard
    Commented Jun 2, 2016 at 9:12
  • 1
    @Wildcard I agree with that. But if we at stackexchange don't make things right, malapropism will take over the world. What you said should be mentioned in the answer.
    – vickyace
    Commented Jun 2, 2016 at 9:29


  1. in direct opposition; being at opposite extremes; complete: diametrical opposites; a diametrical difference.dictionary.com

Two things which are absolute opposites of each other, are diametrically opposed or diametric. We often perceive coins as being diametric, while forgetting that they have a third side: the edge.

  • 1
    Thats a good one. I wonder how that compares to contra. I guess its all in the origins of the words.
    – Joe
    Commented Jun 1, 2016 at 21:12

Try antipodes at dictionary.com

either or both of two opposite things. (from singular "exact or opposite things")

They both are antipodes.

  • 1
    Mmm, that really refers to a specific idea, plus their not opposites though they go by opposite principles, if you know what I mean. Commented Jun 1, 2016 at 20:34
  • @user2901512 what do you mean?
    – vickyace
    Commented Jun 1, 2016 at 20:38
  • 1
    Well, if I was to use the word antipode, it would always refer to two places opposite to each other, I want a word that's more general, though I think you're really homing in on something there. Commented Jun 1, 2016 at 20:40
  • @user2901512 antipodes refer to places, ideas, or anything you want them to. There is nothing more general than this but equivalent or less.
    – vickyace
    Commented Jun 1, 2016 at 20:41
  • 1
    @hkBst Yes, and diametrically so.
    – vickyace
    Commented Jun 2, 2016 at 8:07

The questioner wants a singular noun that denotes a pair of antithetical ideas. I say there is no such word. The professor of English to whom I have been married for fifty years can't think of any. "Antithesis" denotes each in relation to the other. "Dichotomy" denotes the relation between them. "Dilemma" from its Greek roots should mean "two propositions," but it also requires that one of them must be chosen. "Oxymoron" is a conflation of two inconsistent ideas creating an absurdity.

"Dyad" denotes a pair of anything. It's the best I can think of. It's too inclusive, but it does include what the questioner asked for. A dyad is not necessarily a pair of antithetical ideas, but pair of antithetical ideas is a dyad.

  • antithesis : "a person or thing that is the direct opposite of someone or something else." –G
    – Mazura
    Commented Jun 2, 2016 at 20:26
  • Hey Marty, I really appreciate you taking the time to ask your spouse, it's an honor. What do you think of the word, polarities? One thing I will say, is that it may capture the effects of ideas, like say electromagnetism and magnetism, but not the idea itself. If a new word does need to be coined, what would be your opinion on contrapoles? Commented Jun 3, 2016 at 13:00
  • 1
    I thought you wanted a singular noun denoting a pair in a specific relationship. For example, the word "couple" (as in "they're a couple") denotes two people in a certain relationship. A plural noun denoting the same two people would be "partners." Which do you want, singular denoting the coin itself, or plural, denoting its two sides? If a plural, look up the definition of "counterpole."
    – marty39
    Commented Jun 4, 2016 at 0:56

Perhaps polarities

The state of having two opposite or contradictory tendencies, opinions, or aspects:

the polarity between male and female

the Cold War’s neat polarities can hardly be carried on

Oxford Dictionaries Online

  • Sorry, I meant to vote up not down, and the interface didn't let me retract it.
    – JEL
    Commented Jun 2, 2016 at 2:54

EDIT I think dual might be the best term. It is an object (in the most abstract sense) that may have two opposing, mirrored, states.

Thanks to @user2901512's answer below for a hint to this.

Previous answer (incorrect as I initially thought the question asked for the name for two concepts which are opposite to each other, which is not OP's intention, I believe):

How about antonyms? They are words with completely opposite meanings.

If what you mean is "something with two possible values which can be interpreted as exclusive from one another," binary might also work.

  • 2
    In technical usage, "dual" means a counterpart in a pair ("heads is the dual of tails"); "duality" is the pair itself. Commented Jun 2, 2016 at 4:59

A binary oppostion


A binary opposition (also binary system) is a pair of related terms or concepts that are opposite in meaning. Binary opposition is the system by which, in language and thought, two theoretical opposites are strictly defined and set off against one another. It is the contrast between two mutually exclusive terms, such as on and off, up and down, left and right.


Antithesis will also work, although it's very formal. The OED Online's first definition for antithesis is

1. Rhetoric. An opposition or contrast of ideas, expressed by using as the corresponding members of two contiguous sentences or clauses, words which are the opposites of, or strongly contrasted with, each other; as ‘he must increase, but I must decrease,’ ‘in newness of spirit, not in the oldness of the letter’.

One of the examples under that definition is

"In an Antithesis, one contrary must be pronounced louder than the other." (John Mason An essay on elocution, or, pronunciation 1748)

The third definition is also apropos:

  1. By extension: Direct or striking opposition of character or functions (between two things); contrast. Const. of, between (with obs.).

And one of its illustrations:

"The antithesis of natural and revealed religion." (Charles Kingsley · Alton Locke, tailor and poet II. xvii. 262 · 1st edition, 1850)

Apparently the word is from an ancient Greek term, via Latin; it was associated with Logic and Rhetoric all the way through.

Editing to add the second OED definition and my own paraphrase of the definition, per @Mazura's suggestion. I would phrase it as

Antithesis: A pair of opposing or contrasting ideas or things.

As the word in English has gone from a term of art to more general usage it has shifted away from this meaning so that now it's almost always used to mean the distinction between two things, or the second of two opposing things: where once we would have said X is antithetical to Y now we can say X is the antithesis of Y, and we're somewhat less likely to talk about the antithesis of X and Y.

But it certainly can still be used to describe the pair, e.g. X and Y are very different, and this antithesis is at the heart of... etc.

  • I came here to say this one, so have an upvote :)
    – Rob Grant
    Commented Jun 3, 2016 at 17:57
  • This word is in marty39's answer, but it's buried, so plus one. And like that answer, this one would benefit from having a (clearer) definition. antithesis : "a person or thing that is the direct opposite of someone or something else." –G
    – Mazura
    Commented Jun 3, 2016 at 21:43
  • @Mazura: Thanks, I've edited the answer to include my take on the definition.
    – 1006a
    Commented Jun 3, 2016 at 22:17
  • The word was not only buried in my answer, but it was limited to the later meaning of one in relation to the other, A as the antithesis of B. I was unaware of the earlier meaning, A and B as an antithesis. Apparently most of us were unaware of it. It's time to make that meaning better known, outside of the narrow discipline of rhetoric.
    – marty39
    Commented Jun 4, 2016 at 1:09

Duality: ''An instance of opposition or contrast between two concepts or two aspects of something; a dualism.''

However, an instance of opposition between two ideas, isn't strictly the same as the ideas themselves.



Contra is the root as in contradiction.

Edit: I appologize I did not mean to post this I thought I cancelled out. I stopped writing when I re-read the question and thought that this is about what to call the coin, not the concept.

  • How about contracept? :D Commented Jun 1, 2016 at 20:36
  • Thats a good one, I was going that way when I decided to cancel posting. :)
    – Joe
    Commented Jun 1, 2016 at 21:11
  • +1, because I think the best word will have to start with either “contra” or “counter”, such as contrariety”; … contra /counterposition/al”, … “counterpoise”; etc cc: @user2901512
    – Papa Poule
    Commented Jun 1, 2016 at 21:31
  • Also, contrasted : "late 17th century (as a term in fine art, in the sense ‘juxtapose so as to bring out differences in form and color’): from French contraste (noun), contraster (verb), via Italian from medieval Latin contrastare, from Latin contra- ‘against’ + stare ‘stand.’ " –G. As long as we're mentioning words we decided not to post, interestingly, juxtapose was one of mine.
    – Mazura
    Commented Jun 2, 2016 at 2:10
  • in maths, we have co- and contra- if this helps! en.wikipedia.org/wiki/Covariance_and_contravariance_of_vectors
    – JMP
    Commented Jun 2, 2016 at 3:58

If you are talking about a coin with two opposite sides, the sides become a characteristic of the object in question.

Rather than describe the sides, you wish to specify the analogy to the coin itself.

As a coin has two sides, I present "argument" as the term for that which has two sides.

The side lables themselves are of little interest or consequence and can be Pro or Con, Soft or Hard, etc. so long as they appear to be mutually exclusive of the other.


Two antonyms, and a spectrum in between, perhaps?

antonym: a word with a meaning that is opposite to the meaning of another word

source: http://www.merriam-webster.com/dictionary/antonym


Dichotomy. =]

More generally, not limited to two ideas or opposing ones.

Abstract concept or meta concept.

In programming, we usually refer to it as a class, parent class, or abstract.

Note that Abstract concept or meta concept can refer to something with more than two species, and to things that aren't limited to opposing species either.

It's even more general / abstract ;)

  • It may be good to use said term if you wanted to generalize the a number of ideas, and/or the type of ideas, however, the specifics of the question fall under 2 conditions: 1. Two ideas. 2. Opposition. Thus, a term would be needed to refer to two ideas at the same time which are opposites to each other. A term which overrides said conditions would thus be invalid. Commented Jun 5, 2016 at 12:02
  • good catch. Edited.
    – ahnbizcad
    Commented Jun 5, 2016 at 20:37

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