#participant  someone who takes part in an activity
  supertype:  associate  a person who joins with others in some activity; "he had to consult his associate before continuing"
  subtype:  attendee__attendant__attender__meeter  a person who participates in a meeting; "he was a regular attender at department meetings"; "the gathering satisfied both organizers and attendees"
     subtype:  conventioneer  someone who attends a convention
     subtype:  partygoer  someone who is attending a party; "the hall was crowded with an overflow of partygoers"
  subtype:  discussant  a participant in a formal discussion
     subtype:  adducer  a discussant who offers an example or a reason or a proof
  subtype:  bride.participant  a woman participant in her own marriage ceremony
  subtype:  groom__bridegroom  a man participant in his own marriage ceremony
  subtype:  masquerader__masker__masquer  a participant in a masquerade
  subtype:  partaker__sharer  someone who has or gives or receives a part or a share
     subtype:  pooler  someone who shares in and contributes to a general fund for use by all
  subtype:  retreatant  a participant in a religious retreat

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