The definition of a signal is a message or means of communicating a message.(noun)
An example of a signal is a red light.
Signal means out of the ordinary or remarkable.(adjective)
An example of signal used as an adjective is the phrase a "signal win" which means a team that usually loses has just won.
To signal is defined as to communicate or indicate.(verb)
An example of signal is to hold up one finger to mean you'll be there in a minute.
See signal in Webster's New World College Dictionary
Origin: OFr < VL signale < neut. of LL signalis < L signum, a sign
See signal in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Medieval Latin signāle
Origin: , from neuter of Late Latin signālis, of a sign
Origin: , from Latin signum, sign; see sign.
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