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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

Etymology

Origin of incoherent

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

Explanation

Incoherent thoughts don't follow each other logically. Incoherent speech is mumbled or jumbled. Incoherent means that something is difficult to understand because it's not holding together. A lot of people use incoherent to mean unintelligible, which is a perfectly fine usage. But it specifically means unintelligible due to a lack of cohesion, or sticking together. An incoherent argument may sound something like this. "I deserve to go to the dance because it is the second Tuesday of the month and my feet are a size ten." The reasons do not follow each other logically and do not even relate. It's an incoherent mess.

Keep Reading on Vocabulary.com

Vocabulary lists containing incoherent

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.

The regulatory architecture is vast, fragmented and largely incoherent.

From The Wall Street Journal • Mar. 20, 2026

Daniel and his colleagues examined what happens if only the coherent portion of the exiting light is counted as work, while the incoherent portion is treated as heat.

From Science Daily • Dec. 23, 2025

He was discovered by his best friend collapsed on the floor, awake but incoherent.

From Slate • Dec. 8, 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

Some of those in the gathered crowd groaned, while others shouted, incoherent, their words colliding with what others yelled.

From "Anger Is a Gift" by Mark Oshiro