Definition of call sign
: the combination of identifying letters, letters and numbers, or words assigned to an operator, office, activity, vehicle, or station for use in communication (as in the address of a message sent by radio)
First Known Use of call sign
CALL SIGN Defined for English Language Learners
Definition of call sign for English Language Learners
: a combination of letters and numbers that is used to identify someone or something in a radio broadcast
Seen and Heard
What made you want to look up call sign? Please tell us where you read or heard it (including the quote, if possible).