participant (n.) Look up participant at Dictionary.com
1560s, from Middle French participant, from Latin participantem (nominative participans), present participle of participare "to share in, partake of" from particeps "sharing, partaking" (see participation).
participant (adj.) Look up participant at Dictionary.com
1540s, from Latin participantem (nominative participans), present participle of participare "to share in, partake of," from particeps "sharing, partaking" (see participation).