A term used typically to describe a team of people consisting of fewer than the usual number attributed to that group. It can be applied to any similar situation.
Derived largely from the hockey world where players sit on a "bench" when not playing (see benched) and occasionally field a team with fewer teammates than ideally necessary, either due to players not showing up for the game or by the coach's decision.
Even though our playoff finals were on a holiday weekend, we won our championship game despite the short bench.
Due to the last long weekend, we have a short bench at our beach house this coming weekend.