1. to be kept waiting for a long time, usually by someone in power or authority

1. Poor Rocky. I just saw him cooling his heels outside the principal’s office.

2. The assistant had a 3 o’clock appointment with his boss but the boss kept him cooling his heels in the outer office until well past 4:30.

3. I’m sorry I’m late getting home. The professor had me cooling my heels in his office while he was on the telephone.