[n] the act sharing in the activities of a group; "the teacher tried to increase his students' engagement in class activities"
[n] a sense of concern with and curiosity about someone or something; "an interest in music"
[n] a connection of inclusion or containment; "he escaped involvement in the accident"; "there was additional involvement of the liver and spleen"
[n] the condition of sharing in common with others (as fellows or partners etc.)
[n] a usually secretive or illicit sexual relationship