1 difficult to understand; complicated 复杂的: The book has a very involved plot. 这本书的情节非常复杂。

2 (not before a noun 不用于名词前) involved (in sth) closely connected with sth; taking an active part in sth 密切相关；积极参与: I'm very involved in local politics. 我积极投入本地政坛。

3 (not before a noun 不用于名词前) involved (with sb) having a sexual relationship with sb 跟某人有性关系: She is involved with an older man. 她搭上了一个年纪较大的男人。