Reserve

formality and propriety of manner

something kept back or saved for future use or a special purpose

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

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

a district that is reserved for particular purpose

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

the trait of being uncommunicative

hold back or set aside, especially for future use or contingency

give or assign a resource to a particular person or cause

obtain or arrange (for oneself) in advance

arrange for and reserve (something for someone else) in advance