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Synonyms

incoherent

American  
[in-koh-heer-uhnt, -her-] / ˌɪn koʊˈhɪər ənt, -ˈhɛr- /

adjective

  1. without logical or meaningful connection; disjointed; rambling.

    an incoherent sentence.
    Synonyms:
    muddled, irrational, confused

  2. characterized by such thought or language, as a person.

    incoherent with rage.

  3. not coherent or cohering.

    an incoherent mixture.

  4. lacking physical cohesion; loose.

    incoherent dust.

  5. lacking unity or harmony of elements.

    an incoherent public.

  6. lacking congruity of parts; uncoordinated.

  7. different or incompatible by nature, as things.

  8. Physics. (of a wave) having a low degree of coherence.

incoherent British  
/ ˌɪnkəʊˈhɪərənt /

adjective

  1. lacking in clarity or organization; disordered

  2. unable to express oneself clearly; inarticulate

  3. physics (of two or more waves) having the same frequency but not the same phase

    incoherent light
"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

Other Word Forms

  • incoherence noun
  • incoherently adverb

Etymology

Origin of incoherent

First recorded in 1620–30; in- 3 + coherent

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Cannon’s additional reasons to suppress Volume II—beyond her insistence that Smith had no power to compile or submit it—were characteristically incoherent.

From Slate • Feb. 26, 2026

Even light that has become partially incoherent can still perform useful work, just less effectively than fully coherent light.

From Science Daily • Dec. 23, 2025

He said he grew suspicious when someone asked him for a retroactive approval of the order with incoherent documents produced after it was made, and reported this to his superiors.

From Barron's • Nov. 6, 2025

The racial classification structure is incoherent and illogical.

From The Wall Street Journal • Oct. 23, 2025

Over the jumble of voices Lyra heard someone stumble to the door and out, making incoherent sounds of distress.

From "The Golden Compass" by Philip Pullman

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.