An oxymoron (usual plural oxymorons, more rarely oxymora) is a rhetorical device that uses an ostensible self-contradiction to illustrate a rhetorical point or to reveal a paradox. A more general meaning of “contradiction in terms” (not necessarily for rhetoric effect) is recorded by the OED for 1902.
The term is first recorded as latinized Greek oxymōrum, in Maurus Servius Honoratus (c. AD 400); it is derived from the Greek ὀξύς oksús “sharp, keen, pointed” and μωρός mōros “dull, stupid, foolish”; as it were, “sharp-dull”, “keenly stupid”, or “pointedly foolish”. The word oxymoron is autological, i.e. it is itself an example of an oxymoron. The Greek compound word ὀξύμωρον oksýmōron, which would correspond to the Latin formation, does not seem to appear in any known Ancient Greek works prior to the formation of the Latin term.
Antithesis (Greek for “setting opposite”, from ἀντί “against” and θέσις “placing”) is used in writing or speech either as a proposition that contrasts with or reverses some previously mentioned proposition, or when two opposites are introduced together for contrasting effect.Antithesis can be defined as “a figure of speech involving a seeming contradiction of ideas, words, clauses, or sentences within a balanced grammatical structure. Parallelism of expression serves to emphasize opposition of ideas”.An antithesis must always contain two ideas within one statement. The ideas may not be structurally opposite, but they serve to be functionally opposite when comparing two ideas for emphasis.According to Aristotle, the use of an antithesis makes the audience better understand the point the speaker is trying to make. Further explained, the comparison of two situations or ideas makes choosing the correct one simpler. Aristotle states that antithesis in rhetoric is similar to syllogism due to the presentation of two conclusions within a statement.Antitheses are used to strengthen an argument by using either exact opposites or simply contrasting ideas, but can also include both. They typically make a sentence more memorable for the reader or listener through balance and emphasis of the words.
A figure of speech in which two words or phrases with opposing meanings are used together intentionally for effect.
A contradiction in terms.
A proposition that is the diametric opposite of some other proposition.
A device by which two contrasting ideas are juxtaposed in parallel form.