Contestant
/kənˈtestənt/
noun
A person who takes part in a competition or contest.
She was a contestant on a game show.
Often appears as...
game show contestant
beauty pageant contestant
Definition 1 of 2
Pro Tip 1/3Activity Participation
Used when someone is actively taking part in an event, often where skills are tested. 
He became a contestant in the national spelling bee.
Pro Tip 2/3Neutral Tone
The term 'contestant' is neutral, carrying no implication of success or skill level. 
Each contestant received a participation certificate.
Pro Tip 3/3Popular Culture
Commonly used in the context of television and reality shows, where participants compete. 
The contestant went home after the third round of the cooking competition.