1. a gesture, sound, or light that conveys information or instructions
2. an electrical impulse or radio wave transmitted or received
Usage: technical

1. to make a gesture or sound to convey information or give an instruction
2. to be a sign or indication of something

1. notable or striking; used for emphasis

Examples

• The traffic light turned red as a signal to stop.
• She raised her hand to signal the waiter.
• The radio signal was weak in the mountains.
• Dark clouds signal an approaching storm.
• The team’s victory was a signal achievement.
• He signaled left before turning the corner.
• The smoke signal could be seen for miles.