Oxymoron

An oxymoron (/ɒksi:mɔ:rɒn/; plural oxymora (/ɒksi:mɔ:rə/) or oxymorons (/ɒksi:mɔ:rɒnz/)) is a rhetorical device that uses an ostensible self-contradiction to illustrate a rhetorical point or to reveal a paradox.