empty seat
nounUK /ˈɛmpti siːt/
US /ˈɛmpti sit/
A seat with no one sitting in it.
There was an empty seat next to me on the bus.
OTHER MEANINGS
2. A position or role that no one has filled yet.
The team still has an empty seat on the coaching staff.
3. A missing person's usual place, felt as a loss.
At dinner, the empty seat reminded them of their grandfather.
4. An unused place in a class, event, or group.
The school filled every empty seat by the first week.