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neologism

[nee-ol-uh-jiz-uh m]

noun

a new word, meaning, usage, or phrase.
the introduction or use of new words or new senses of existing words.
a new doctrine, especially a new interpretation of sacred writings.
Psychiatry. a new word, often consisting of a combination of other words, that is understood only by the speaker: occurring most often in the speech of schizophrenics.

Origin of neologism

From the French word néologisme, dating back to 1790–1800. See neology, -ism
Related formsne·ol·o·gist, nounne·ol·o·gis·tic, ne·ol·o·gis·ti·cal, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for neologistic

neologism

neology

noun plural -gisms or -gies

a newly coined word, or a phrase or familiar word used in a new sense
the practice of using or introducing neologisms
rare a tendency towards adopting new views, esp rationalist views, in matters of religion
Derived Formsneologist, nounneologistic, neologistical or neological (ˌnɪəˈlɒdʒɪkəl), adjectiveneologistically or neologically, adverb

Word Origin for neologism

C18: via French from neo- + -logism, from Greek logos word, saying
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for neologistic

neologism

n.

"practice of innovation in language," 1776, from French néologisme, from neo- (see neo-) + Greek logos "word" (see lecture (n.)). Meaning "new word or expression" is from 1803. Neological is attested from 1754.

Online Etymology Dictionary, © 2010 Douglas Harper
neologistic in Medicine

neologism

[nē-ŏl′ə-jĭz′əm]

n.

A meaningless word used by a psychotic.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.