Noun
1. formality and propriety of manner
2. something kept back or saved for future use or a special purpose
3. an athlete who plays only when another member of the team drops out
4. (medicine) potential capacity to respond in order to maintain vital functions
5. a district that is reserved for particular purpose
6. armed forces that are not on active duty but can be called in an emergency
7. the trait of being uncommunicative; not volunteering anything more than necessary