Merriam-Webster Collegiate Dictionary - reserve

 I. transitive verb  (~d; reserving)  Etymology: Middle English, from Anglo-French ~r, from Latin reservare, literally, to keep back, from re- + servare to keep — more at conserve  Date: 14th century  1.  a. to hold in ~ ; keep back ~ grain for seed  b. to set aside (part of the consecrated elements) at the Eucharist for future use  c. to retain or hold over to a future time or place ; defer ~ one's judgment on a plan  d. to make legal reservation of  2. to set or have set aside or apart ~ a hotel room  Synonyms: see keep  • reservable adjective  II. noun  Usage: often attributive  Date: 1648  1. something ~d or set aside for a particular purpose, use, or reason: as  a.  (1) a military force withheld from action for later decisive use — usually used in plural  (2) forces not in the field but available  (3) the military forces of a country not part of the regular services; also reservist  b. a tract (as of public land) set apart ; reservation  2. something stored or kept available for future use or need ; stock  3. an act of reserving ; qualification  4.  a. restraint, closeness, or caution in one's words and actions  b. forbearance from making a full explanation, complete disclosure, or free expression of one's mind  5. archaic secret  6.  a. money or its equivalent kept in hand or set apart usually to meet liabilities  b. the liquid resources of a nation for meeting international payments  7. substitute  8. ~ price  9. a wine made from select grapes, bottled on the maker's premises, and aged differently from the maker's other wines of the same vintage