drum·mer 
/ˈdrʌmɚ/ noun
plural drum·mers /ˈdrʌmɚ/ noun [count] : a person who plays a drum or a set of drums
▪ The band got a new drummer.
▪ The band got a new drummer.
different drummer
US — used in phrases like march to the beat of a different drummer to describe a person who thinks, lives, or behaves in an unusual way ▪ His strange behavior was no surprise—he had always marched to (the beat of) a different drummer. [=done things differently from other people] ▪ Her friends went to college, but she heard a different drummer and moved to the city to be an actor.
