key
1. key \'ke-\ n [ME, fr. OE c-g; akin to MLG keige spear] 1a: a usu.
metal instrument by which the bolt of a lock is turned 1b: any of various
devices having the form or function of such a key 2: a means of gaining or
preventing entrance, possession, or control 3a: something that gives an
explanation or provides a solution 3b: a list of words or phrases giving
an explanation of symbols or abbrevia tions 3c: an arrangement of the
salient characters of a group of plants or animal s or of taxa designed to
facilitate identification 3d: a map legend 4a1: COTTER PIN 4a2: COTTER
4b: a keystone in an arch 4c: a wedge used to make a dovetail joint 4d: a
small parallel-sided piece that fits into a groove and prevents relat ive
motion between rotating parts; also : a wedge for drawing or holding parts
together 5a: one of the levers of a keyboard musical instrument that
actuates the me chanism and produces the tones 5b: a lever that controls a
vent in the side of a woodwind instrument or a valve in a brass instrument
5c: a depressible digital that serves as one unit of a keyboard and that wo
rks usu. by lever action to set in motion a character or an escapement (as
in some typesetting machines) 6: SAMARA 7: a leading individual or
principle 8: a system of seven tones based on their relationship to a
tonic; speci f : the tonality of a scale 9a: characteristic style or tone :
STRAIN 9b: the tone or pitch of a voice 9c: the predominant tone of a
photograph with respect to its lightness or d arkness 10: a decoration or
charm resembling a key 11: a small switch for opening or closing an
electric circuit
2. key vt 1: to lock with a key : as 1a: to secure (as a pulley on a
shaft) by a key 1b: to finish off (an arch) by inserting a keystone 2: to
regulate the musical pitch of 3: to make conformable : ATTUNE 4: to
identify (a biological specimen) by a key 5: to insert in (an
advertisement) matter intended to identify answers 6: to make nervous or
tense - usu. used with up : to use a key
3. key aj : of basic importance : FUNDAMENTAL
4. key n [Sp cayo, fr. Lucayo] : a low island or reef; specif : one of the
coral islets off the s outhern coast of Florida
Webster's English Dictionary