What is the meaning of involvement?

noun

• The act of sharing in the activities of a group.
  • usage: "the teacher tried to increase his students' engagement in class activities"
  • synonyms: engagement, participation, involution
• A connection of inclusion or containment.
  • usage: "he escaped involvement in the accident"; "there was additional involvement of the liver and spleen"
• A sense of concern with and curiosity about someone or something.
  • usage: "an interest in music"
  • synonyms: interest
• A usually secretive or illicit sexual relationship.
  • synonyms: affair, affaire, intimacy, liaison, amour
• The condition of sharing in common with others (as fellows or partners etc.. ).
  • synonyms: participation