Emily Dickinson Lexicon

RES-ERV-A'TION, n. [s as z. Fr. from L. reservo.]

1. The act of reserving or keeping back or in the mind; reserve; concealment or withholding from disclosure; as, mental reservation.
2. Something withheld, either not expressed or disclosed, or not given up or brought forward. With reservation of a hundred knights. – Shak. In the United States, a tract of land not sold with the rest, is called a reservation.
3. Custody; state of being treasured up or kept in store. – Shak.
4. In law, a clause or part of an instrument by which something is reserved, not conceded or granted; also, a proviso. Mental reservation is the withholding of expression or disclosure of something that affects a proposition or statement, and which if disclosed, would materially vary it import. Mental reservations are the refuge of hypocrites. – Encyc.