Meaning & Definition
verb
To weaken or damage something, especially a function or ability.
Chronic alcohol consumption can impair mental faculties.
To make worse or less effective.
The heavy rain may impair visibility on the roads.
To cause a reduction in strength or quality.
Injury can impair an athlete's performance.
Etymology
Middle English, from Old French 'empaïr', from 'em-' (to make) + 'pair' (harmful, defective).
Common Phrases and Expressions
impair one's capabilities:
to reduce someone's abilities or effectiveness.
impairment of vision:
the condition of having reduced visual function.
Slang Meanings
to mess up
Don't impair the plans we made.
to screw up
He really impaired the project with his mistakes.