participant      
noun [ C ] uk/pɑːˈtɪs.ɪ.pənt/ us/pɑːrˈtɪs.ə.pənt/
C1 参加者,参与者
a person who takes part in or becomes involved in a particular activity
 - More examples
 - The games is an international sporting event with more than three thousand participants.
 - She has been an active participant in the discussion.
 - The students claim to be willing participants in the experiment.
 - We were participants in a live debate on television.
 - The majority of course participants find subsequent employment.