attendee

Concise Oxford English Dictionary © 2008 Oxford University Press:
attend/əˈtend/

▶verb

• 1 be present at.

  ■ go regularly to (a school, church, or clinic).

• 2 (attend to) deal with.

  ■ pay attention to.

• 3 occur at the same time as or as a result of.

• 4 escort and wait on (a member of royalty or other important person).

– derivatives
attendee noun,
attender noun.

– origin ME: from OFr. atendre, from L. attendere, from ad- ‘to’ + tendere ‘stretch’.