Impair

Part of speech: noun (n.)

Diminution; injury. [Obs.]

Part of speech: verb (v.)

To make worse; to diminish in quantity, value, excellence, or strength; to deteriorate; as, to impair health, character, the mind, value. Time sensibly all things impairs. Roscommon. In years he seemed, but not impaired by years. Pope.

Synonyms: diminish; decrease; injure; weaken; enfeeble; debilitate; reduce; debase; deteriorate.

Part of speech: verb (v.)

To grow worse; to deteriorate. Milton.

Part of speech: adjective (a.)

Not fit or appropriate. [Obs.]