participant; entrant; player; competitor
General term for someone who takes part in an event, meeting, competition, or activity. Covers attendees, contestants, and players.
All participants in the meeting must register in advance.
トーナメントの参加者は32名です。
There are 32 entrants in the tournament.
They are recruiting participants for the marathon.
The number of participants increased significantly this year's event.
They handed out pamphlets to the participants at the reception desk.
She gave a speech as a participant.