(music) An indication of the key of a composition, giving the number of sharps or flats in the corresponding scale.

(computing) To take something as a controlling input datum. / To turn off something (e.g. a car) using a key.

(cryptography) An exchange of peers' keys at the initialization phase of connection.

(music) A musical key based upon a major scale. / (idiomatic) A mood of cheerfulness or happiness.

(idiomatic) In an unrestrained manner; on a large or expansive scale.

(music) A musical key based upon a minor scale. / (idiomatic) A mood of melancholy or pathos.

(idiomatic) In a restrained manner; on a small or limited scale.

An item carried on a key ring either as decoration or security.

One of the two keys used in asymmetric cryptography, which is published to others, unlike the private key.

Alternative spelling of keyserver