reserve

Give or assign a resource to a particular person or cause.

Obtain or arrange (for oneself) in advance.

“We managed to reserve a table at Maxim's”

Arrange for and reserve (something for someone else) in advance.

“reserve me a seat on a flight”

Hold back or set aside, especially for future use or contingency.

(medicine) potential capacity to respond in order to maintain vital functions.

Something kept back or saved for future use or a special purpose.

A district that is reserved for particular purpose.

The trait of being uncommunicative; not volunteering anything more than necessary.

Armed forces that are not on active duty but can be called in an emergency.

An athlete who plays only when a starter on the team is replaced.

Formality and propriety of manner.