tr.v. im·paired, im·pair·ing, im·pairs
To cause to weaken, be damaged, or diminish, as in quality: an injury that impaired my hearing; a severe storm impairing communications.
[Middle English empairen, from Old French empeirer, from Vulgar Latin *impēiōrāre : Latin in-, causative pref.; see IN-2 + Latin pēior, worse; see ped- in the Appendix of Indo-European roots.]
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