1) Actor 2) Applicant 3) Attendee 4) Ballplayer 5) Contestant 6) Discussant 7) Fighter 8) Footballer 9) Golfer 10) Grandmaster 11) Groom 12) Linksman 13) Masker 14) Masquer 15) Masquerader 16) Meeter 17) Mvp 18) Partaker 19) Party 20) Player 21) Retreatant 22) Scorer 23) Sharer 24) Sportsperson 25) Stringer 1) Associate 2) French word used in English 
• (n.) A participator; a partaker. • (a.) Sharing; participating; having a share of part.
[Noun] Plural form: participants. Someone who takes part in something, for example, a game or a quiz.
A party of a funding. It usually refers to the lowest rank or smallest level of funding.
A person who is eligible to receive health benefits under a health benefits plan. This term may refe
Par·tic'i·pant adjective [ Latin participans , present participle of participare : confer French participant . See Participate .] Sharing; participating; having a share of part. Bacon. 
Participant: 1. In a clinical trial, someone who takes part in it. A participant may or may not have a disease. The term participant in this regard is synonymous with the term subject. 2. In health care benefits, a person who is eligible to receive health benefits under a health benefits plan. The term participant in this regard may refer to the em...
Study participant.
[n] - someone who takes part in an activity
noun someone who takes part in an activity
means an individual who has been determined to be eligible to participate in and who is receiving services (except follow-up services authorized under this title) under a program authorized by this title. Participation shall be deemed to commence on the first day, following determination of eligibility, on which the individual began receiving subs...
a person who takes part in or is skilled at some game