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

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.

Example Sentences

“That is imperfect advice, but probably better than the uncertainty of travel right now,” he said.

From Los Angeles Times • May 22, 2026

Apple is making hit products and high profits from imperfect chips.

From MarketWatch • May 18, 2026

Some law enforcement agencies argue that acting on imperfect signals is preferable to missing serious risks.

From Salon • May 12, 2026

It is imperfect, but it is the best system we have for turning raw claims into reliable knowledge.

From Slate • May 3, 2026

Knowledge, of course, is always imperfect, but it seemed to me that when a nation goes to war it must have reasonable confidence in the justice and imperative of its cause.

From "The Things They Carried" by Tim O'Brien

Related Words

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