impair

Etymology

From Middle English impairen, empeiren, from Old French empeirier, from Early Medieval Latin impeiōrāre, from in- + Late Latin peiōrāre (“worsen”), from peiōrem (“worse”), comparative of malus (“bad”).

verb

1. (transitive) To weaken; to affect negatively; to have a diminishing effect on.
   In 2016, it was announced that Jones had been diagnosed with primary progressive aphasia, a form of dementia that impairs the ability to communicate. January 22, 2020, Stuart Jeffries, “Terry Jones obituary”, in The Guardian
2. (intransitive, archaic) To grow worse; to deteriorate.

adj

1. (obsolete) Not fit or appropriate; unsuitable.

noun

1. (obsolete) The act of impairing or deteriorating.
2. (obsolete) The fact of being impaired or having grown worse.
3. (obsolete) An impairment or deterioration.
   Suppoſe a mans credit ſhould ſuffer an impair with thoſe whoſe cenſure is not to be valued; yet think, which is worſe, ſhame or ſin? Wilt thou ſin againſt God to ſave thy credit? 1671, Thomas Watson, The Beatitudes, pages 146–147