I. ˈsignəl, -n ə l noun
( -s )
Etymology: Middle English, from Middle French seignal, segnel, signal, from Medieval Latin signale, from Late Latin, neuter of signalis of a sign, from Latin signum sign + -alis -al — more at sign
1. obsolete : emblem , symbol
2. archaic : token , indication
in signal of my love to thee — Shakespeare
3.
a. : an act, event, or watchword that has been agreed upon as the occasion of concerted action
signal fires of rebellion
b. : something that incites to action : an immediate cause or impulse
his remark was the signal for a storm of weeping
4.
a. : a sound or gesture made to give warning or command
signal that warns of an air raid
waiting for the signal to open fire
b. : an object placed to convey notice or warning: as
(1) : a device (as a colored light) for regulating vehicular or pedestrian traffic
(2) : a device used to warn trainmen or persons approaching a railroad of danger or to convey orders or information to a train crew
5. : an object (as a flag on a pole) centered over a point so as to be observed from other positions in surveying
6.
a. : an identifying tab (as of a thumb index) fastened to a book leaf at its fore edge
b. : a small projecting tab that attaches to the edge of a card or folder as an aid in filing or indexing
7. : a play indicating to one's partner in a card game that one holds certain cards or desires a certain play
8. : the beam of light reflected from the face of a crystal rotated into a particular position in a goniometer
9.
a. : an object used to transmit or convey information beyond the range of human voice
flying a flag as a distress signal
b. : the intelligence, message, sound, or image conveyed in telegraphy, telephony, radio, radar, or television
c. : a detectable physical quantity or impulse (as a voltage, current, magnetic field strength) by which messages or information can be transmitted
10. : a speech sound or form or combination of sounds and forms that communicates a meaning or a difference in meaning — compare morpheme , phoneme
II. verb
( signaled or signalled ; signaled or signalled ; signaling or signalling ; signals )
transitive verb
1. : to notify by a signal : make a signal to
signaled his wife to leave the room
signaled the fleet to turn back
2.
a. : to communicate (a message) by signals
signal orders to a field unit
b. : announce by signal
the ship signaled her departure with warning blasts on the whistle
c. : to determine or fix (meaning) in a speech utterance
the kind of sentence … is signaled by special contrastive patterns in the arrangement of … parts of speech — C.C.Fries
: constitute a characteristic feature of (a meaningful linguistic form)
plurality is usually signaled by s
3. : signalize
waiter with tray signals a café — National Geographic
intransitive verb
: to make or send a signal
frantically signaling with both arms
III. adjective
Etymology: modification of French signalé, past participle of signaler to distinguish, from Old Italian segnalare to signal, distinguish, from segnale signal, from Medieval Latin signale
1. : distinguished from what is ordinary : noticeable , outstanding
signal achievement
students of signal promise
signal experience
2. : significative , distinctive
signal markings
3. : employed or used in signaling
signal beacon
signal flags
signal corps
Synonyms: see noticeable