What does "reservation" mean?

Additional senses

1. 2.A tract of the public land reserved for some special use, as for schools, for the use of Indians, etc. [U.S.]
2. 3.The state of being reserved, or kept in store. Shak.
3. 4.(Law) (a) A clause in an instrument by which some new thing is reserved out of the thing granted, and not in esse before. (b) A proviso. Kent. Note: This term is often used in the same sense with exception, the technical distinction being disregarded.
4. 5.(Eccl.) (a) The portion of the sacramental elements reserved for purposes of devotion and for the communion of the absent and sick. (b) A term of canon law, which signifies that the pope reserves to himself appointment to certain benefices. Mental reservation, the withholding, or failing to disclose, something that affects a statement, promise, etc., and which, if disclosed, would materially change its import.