a. Having a temper not easily excited; free from passion; unshakably calm and collected. -- Cool"-head`ed*ness, n. Syn. -- cool, imperturbable, unflappable. [1913 Webster + WordNet 1.5]
adj. made or become cool or made cool as specified; often used as a combining form; as, air-cooled auto engine; the cooled milk was put in the refrigerator. [ WordNet 1.5 ]