1. a. A chain, rope, or strap attached to the collar or harness of an animal, especially a dog, and used to lead it or hold it in check.
b. A strap or cord attached to a harness worn by a small child, used to prevent the child from wandering off.
c. A strap, cord, or other line used to keep an object close to its user or in a designated location.
2. a. Control or restraint: emotions kept in leash.
b. A range of allowable behavior or responsibility: a husband kept on a short leash.