There are several synonyms for the phrase "kick your heels," which means to wait or pass time idly. One popular synonym is "twiddle your thumbs," meaning to do nothing while waiting. Another similar phrase is "sit on your hands," which can mean waiting patiently without taking action. People may also say "hang around," "loiter," or "lounge" to describe the act of waiting or passing time leisurely. In a more formal setting, "stand-by" or "remain on standby" may be used. Each of these synonyms describes a sense of waiting or passing time, often with an implication of impatience or boredom.