The figure of speech that combines two contradictory terms, as in “deafening silence,” is an oxymoron.
An oxymoron places apparently incompatible words together to create a striking expression. “Deafening silence” suggests silence so intense that it feels overwhelming, while phrases such as “bittersweet,” “living dead,” and “open secret” use contradiction to compress a complex idea into a few words.
The word itself is an example of the device. It comes from Greek roots meaning roughly “sharp” and “dull,” producing the self-contradictory sense of “sharp-dull.” The term was recorded in Latinized Greek by the Roman grammarian Maurus Servius Honoratus around AD 400.
Oxymoron is often confused with paradox. An oxymoron usually joins contradictory words in a compact phrase, while a paradox is a broader statement or idea that appears contradictory but may reveal a deeper truth. Antithesis, by contrast, places contrasting ideas in balanced structures without requiring them to contradict one another.