any nonverbal action or gesture that encodes a message;
"signals from the boat suddenly stopped"
例句
用作名词(n.)
I failed to yield at a crosswalk, I changed lanes at the intersection, I changed lanes without signaling while running a red light and speeding!没有在人行横道处让行，在路口换道，在闯红灯和超速时换道没打信号！
She was signaling wildly, waving her arms.她奋力挥臂发信号。
