Longman Dictionary of Contemporary English - involved

~ adj 1 be involved to take part in an activity or event, or be connected with it in some way + in  (More than 30 software firms were involved in the project.) deeply/heavily involved (=be involved a lot)  (At law school Hilary became heavily involved in student politics. | get involved in an argument/discussion/fight etc)  (I don't want to get involved in some lengthy argument about who is to blame. | The Mafia could well be involved.) 2 be involved in an accident/fight/crash etc to be one of the people in an accident, crash etc  (I'm afraid your son's been involved in an accident.) 3 work/effort etc involved in doing sth the work, money, effort, risk etc that is involved in doing something is the amount that is needed in order to succeed in doing it  (Most people don't realize the amount of effort that is involved in writing a novel. | I would never go climbing on my own - there's too much risk involved.) 4 be involved with sb to be having a sexual relationship with someone, especially someone you should not have a relationship with  (Matt's involved with a married woman at work.) 5 having so many different parts that it is difficult to understand; complicated  (The plot was so involved that very few people knew what was going on.)