Neologism can refer either to a new word or expression or to a new meaning of an existing word.

// I love seeing all the slangy neologisms that pop up on social media every year.

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"… [U]ndertakers refashioned themselves … as funeral directors over the span of a few decades in the early twentieth century. … [T]he new generation of morticians (another neologism meant to conjure expertise) bought up shambling Victorian mansions in swish residential districts and invented a new form of comfort." — Dan Piepenbring, Harper's, 2 Feb. 2024

The English language is constantly picking up neologisms. In recent decades, for example, social media has added a number of new terms to the language. Finsta, rizz, influencer, meme, and doomscroll are just a few examples of modern-day neologisms that have been integrated into American English. The word neologism was itself a brand-new coinage in the latter half of the 18th century, when English speakers borrowed the French term néologisme, meaning both "the habit of forming new words" and "a newly formed word." The French term, which comes from néologie, meaning "coining of new words," comprises familiar elements: we recognize our own neo-, with various meanings relating to what is new, as in neoclassical, and -logy, meaning "oral or written expression," as in trilogy.