From WordNet (r) 3.0 (2006) [wn]:
performer
n 1: an entertainer who performs a dramatic or musical work for
an audience [syn: performer, performing artist]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Performer \Per*form"er\, n.
One who performs, accomplishes, or fulfills; as, a good
promiser, but a bad performer; especially, one who shows
skill and training in any art; as, a performer of the drama;
a performer on the harp.
[1913 Webster]