1. The children were ready to go, but their father was not. They kept bothering him until he told them to hold their horses.
2. Now just hold your horses I know you’re in a hurry, but you can’t go outside without your coat on in this chilly weather.

Synonym: keep (one’s) shirt on. Antonyms: shake a leg; step on it. The expression is generally used in the imperative. It is used by an adult to children, a superior to an inferior or between two equals on friendly or intimate terms.