I. ˈkēiŋ-ē.ēŋ noun
( -s )
Etymology: key (I) + -ing (n. suffix)
: the process of turning an electronic circuit off or on either manually or automatically
such keying represents the simplest possible form of modulation, and is applicable to all kinds of oscillators — W.A.Edson
II. adjective
: possessing the ability to turn an electronic circuit off or on
a keying device