Emily Dickinson Lexicon

IM-PAIR', v.t. [Fr. empirer; Sp. empeorar; Port. empeiorar, from peior, worse, Sp. peor, Fr. pire, from L. pejor.]

1. To make worse; to diminish in quantity, value or excellence. An estate is impaired by extravagance or neglect. The profligate impairs his estate and his reputation. Imprudence impairs a man's usefulness.
2. To weaken; to enfeeble. The constitution is impaired by intemperance, by infirmity and by age. The force of evidence may be impaired by the suspicion of interest in the witness.