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imperfect

American  
[im-pur-fikt] / ɪmˈpɜr fɪkt /

adjective

  1. relating to or characterized by defects or weaknesses.

    With my imperfect vision I couldn’t make out the street name.

    Synonyms:
    faulty, defective
  2. not perfect; lacking completeness.

    Human knowledge on all subjects is imperfect.

    Synonyms:
    immature, underdeveloped, incomplete
    Antonyms:
    complete
  3. Grammar. designating a verb aspect, tense, or other verb category used to express an action or state still in process at some point of reference in time, especially in the past.

  4. Law. being without legal effect or support; unenforceable.

  5. Botany. (of a flower) diclinous.

  6. Music. of or relating to the interval of a major or minor third or sixth.


noun

Grammar.
    1. in some languages, a verb aspect, tense, or other verb category used to express an action or state still in process at some point of reference in time, especially in the past.

    2. an instance or form of a specific verb in such an aspect, tense, or construction, such as Latin portābam “I was carrying.”

imperfect British  
/ ɪmˈpɜːfɪkt /

adjective

  1. exhibiting or characterized by faults, mistakes, etc; defective

  2. not complete or finished; deficient

  3. botany

    1. (of flowers) lacking functional stamens or pistils

    2. (of fungi) not undergoing sexual reproduction

  4. grammar denoting a tense of verbs used most commonly in describing continuous or repeated past actions or events, as for example was walking as opposed to walked

  5. law (of a trust, an obligation, etc) lacking some necessary formality to make effective or binding; incomplete; legally unenforceable See also executory

  6. music

    1. (of a cadence) proceeding to the dominant from the tonic, subdominant, or any chord other than the dominant

    2. of or relating to all intervals other than the fourth, fifth, and octave Compare perfect

"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

noun

  1. grammar

    1. the imperfect tense

    2. a verb in this tense

"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 imperfect

First recorded in 1300–50; from Latin imperfectus “unfinished”; equivalent to im- 2 + perfect; replacing Middle English imparfit, from Middle French imparfait, from Latin, as above

Explanation

Something imperfect has flaws, errors, or problems. Imperfect is the opposite of perfect. Imperfect comes from the Latin word imperfectus, meaning “incomplete." If you have an imperfect knowledge of French, you might be able to order a coffee in Paris but not chat with the waiter. Something imperfect is unfinished or damaged in some way. Scuffed silver shoes are imperfect. A great baseball player who makes one error is imperfect. Getting 100 on a test is perfect, but getting a 98 is imperfect. If it’s lacking something, it’s imperfect.

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Vocabulary lists containing imperfect

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:

Wolff is an imperfect source; he’s previously been accused of making up quotes.

From Slate Aug. 21, 2026

Munns, the potato farmer, said more people should try buying imperfect veg if they see it in the supermarket aisle this year.

From BBC Aug. 11, 2026

“We know that the amount of overseas earnings has grown tremendously, so it’s an imperfect measure,” says Jonas Svallin, senior director for buy-side research at FactSet.

From The Wall Street Journal Aug. 3, 2026

“You are dealing with imperfect information. So the mindset is to take down the exposure if it is the beginning of the end. We have a short leash on these stocks,” he said.

From MarketWatch Jul. 27, 2026

That said, the treatment is imperfect, and there are still many questions to be answered.

From "At Last She Stood" by Erin Entrada Kelly

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