signal
A2Գոյական/US /sˈɪɡnəl/ SĬGN-əl; UK /sˈɪɡnəl/ SĬGN-əl/
A sign made for the purpose of giving notice to a person of some occurence, command, or danger; also, a sign, event, or watchword, which has been agreed upon as the occasion of concerted action.
