seat

back/rear/front seat =the back or front seat in a car 

 driver's seat  

passenger seat  =the seat next to the driver's seat in a car

window/aisle seat  =a seat next to the window or aisle, for example on a plane

 empty/vacant seat front-row seat  =in a theatre, sports ground etc

 good seat  =one from which you can see well

ringside seat  =a seat in the front row for a sports event, especially a boxing match  

have/take a seat   

show somebody to their seat  

book/reserve a seat  

bums on seats British English informal (=used for talking about the number of people who go to an event, especially if this is a lot of people)