v. 1 tr. & intr. make or become hard or harder. 2 intr. & tr. become, or make (one's attitude etc.), uncompromising or less sympathetic. 3 intr. (of prices etc.) cease to fall or fluctuate. harden off inure (a plant) to cold by gradual increase of its exposure. hardener n.
HARDEN
Meaning of HARDEN in English
Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012