1. to mean or represent something
2. to be a sign or indication of something
3. to be important or have meaning

Examples

• The red light signifies danger.
• What does this symbol signify?
• Dark clouds often signify an approaching storm.
• Her silence seemed to signify agreement.
• The handshake signified the end of their dispute.
• Does this discovery signify a breakthrough in medicine?
• The results don’t signify much without more data.