noun / verb
reserve
rih-ZURV/rɪzˈɝv/
Something kept available for later use.
The man keeps one water bottle in reserve while using the other.

Etymology
The pieces express “keeping back”: something reserved is withheld from immediate or general use. That makes it available later, or keeps it apart for a particular person.
In context
remember to reserve them for informal or semiformal occasions as they are not a replacement for traditional dress shoes in strictly formal contexts.
More examples
- Our food reserves last through the winter.
- Reserve half the sauce for tomorrow's dinner.
- She keeps some energy in reserve for the final mile.
Forms
reserve · reserves · reserved · reserving
Similar words
- stockpile
- Usually emphasizes a large supply accumulated for future needs.
- supply
- An available quantity, not necessarily set aside for later.