11 letters · 17 points in Scrabble
noun someone who takes part in an activity
noun a person who participates in or is skilled at some game
originFrom stem of particip(ate) + -ant, borrowed from Middle French participant, from Latin participāns, present participle of participō; see participate. Displaced native Old English dǣlnimend (literally “part taker”).
Etymology from Wiktionary, CC BY-SA 3.0