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Synonyms

incoherent

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

adjective

  1. An image of the word incoherent as defined by without logical or meaningful connection; disjointed; rambling.

    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.

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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.

See Examples For:

There’s 60 incoherent parts posted on TikTok and 24.3 million views.

From Slate ● Sep. 26, 2026

“Unless you’re going to throw everything out and start over again, you’re going to have a very incoherent thing. Unless you have a clear strategy, you’re going to have some apples and oranges.”

From Salon ● Sep. 25, 2026

Maybe a young Mexican singer could shed some illumination, I thought, before sending a somewhat incoherent email to Silvana Estrada.

From Los Angeles Times ● Aug. 25, 2026

In those experiments, they used an LED, an incoherent light source, to produce polarization-entangled photons.

From Science Daily ● Aug. 8, 2026

Among other plots, Harvey attempted to damage Castro's public image by adding chemicals to his cigars that would have made him seem confused and incoherent.

From "Spies: The Secret Showdown Between America and Russia" by Marc Favreau

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