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.

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noun

Grammar.

1. 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

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noun

1. grammar

   1. the imperfect tense

   2. a verb in this tense

Other Word Forms

• imperfectly adverb
• imperfectness noun

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

Example Sentences

Each one was slightly imperfect, dusted generously with cinnamon.

From Salon • Mar. 17, 2026

The San Fernando Valley native is a brilliant director who has made sprawling, messy epics about imperfect people synonymous with his name, like John Ford with Westerns or A24 with art house flicks.

From Los Angeles Times • Mar. 17, 2026

Both approaches can miss events, depend on imperfect memory, and cannot record gas production while someone is asleep.

From Science Daily • Mar. 14, 2026

“Cost allocation for transmission has always been a very complex and difficult question. It’s an imperfect science.”

From The Wall Street Journal • Mar. 13, 2026

If this really were a new star, it would shatter that perfection—and once you accepted that the heavens were imperfect, who could say what might follow?

From "The Scientists" by John Gribbin

Related Words

• immature
• incomplete
• inexact
• rudimentary
• sketchy
• warped