Open English Wordnet
Nouns
(n)reservation, qualificationa statement that limits or restricts some claim“he recommended her without any reservations”
(n)mental reservation, reservation, arriere penseean unstated doubt that prevents you from accepting something wholeheartedly
(n)booking, reservationthe act of reserving (a place or passage) or engaging the services of (a person or group)“wondered who had made the booking”
(n)reservationthe written record or promise of an arrangement by which accommodations are secured in advance