unreserved

Not reserved: not otherwise or already committed.

an unreserved forest

Not booked in advance: with no reservation.

an unreserved table

For the steam services, passengers with reserved seats are assembled behind the appropriate notice boards in the centre cab road, which is barred to motor traffic on summer Saturdays. Unreserved passengers line up behind other boards, which merely display destinations and not departure times.

Without reserve: unrestrained, unconstrained.

an unreserved demeanor