unreserve

From un- +‎ reserve.

unreserve (countable and uncountable, plural unreserves)

1. (uncountable) A lack or absence of reserve; frankness; uninhibitedness. [from 18th c.]
   • c. 1792–3, Jane Austen, ‘Catharine, or The Bower’, Juvenilia:

     Kitty, tho' perhaps not authorized to address him with so much familiarity on so short an acquaintance, could not forbear indulging the natural Unreserve and Vivacity of her own Disposition, in speaking to him, as he spoke to her.

2. (countable, India) A forest that is not set aside as a reserve.

unreserve (third-person singular simple present unreserves, present participle unreserving, simple past and past participle unreserved)

1. (transitive, chiefly computing) To undo or cancel a reservation.

• unreservation

• revenuers, unreverse