Mental reservation

Reservation Res`er*va"tion (r?z`?r-v?"sh?n), n. [Cf. F. r['e]servation, LL. reservatio. See {Reserve}.] 1. The act of reserving, or keeping back; concealment, or withholding from disclosure; reserve. --A. Smith. [1913 Webster]

With reservation of an hundred knights. --Shak. [1913 Webster]

Make some reservation of your wrongs. --Shak. [1913 Webster]

2. Something withheld, either not expressed or disclosed, or not given up or brought forward. --Dryden. [1913 Webster]

3. A tract of the public land reserved for some special use, as for schools, for the use of Indians, etc. [U.S.] [1913 Webster]

4. The state of being reserved, or kept in store. --Shak. [1913 Webster]

5. (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. [1913 Webster]

Note: This term is often used in the same sense with exception, the technical distinction being disregarded. [1913 Webster]

6. (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. [1913 Webster]

7. an agreement to have some space, service or other acommodation, as at a hotel, a restaurant, or on a public transport system, held for one's future use; also, the record or receipt for such an agreement, or the contractual obligation to retain that accommodation; as, a hotel reservation; a reservation on a flight to Dallas; to book a reservation at the Ritz. [PJC]

{Mental reservation}, the withholding, or failing to disclose, something that affects a statement, promise, etc., and which, if disclosed, would materially change its import. [1913 Webster]