(+ object)
to make (something) weaker or worse
Smoking can impair your health.
His memory was so impaired by age that he often forgot where he was.
Drinking impairs a person’s ability to think clearly.
– impaired adjective (more impaired; most impaired)
The disease causes impaired vision/hearing in elderly people.
– sometimes used in combination
hearing-impaired people (=people with impaired hearing)