WordWeb Online

1. The time when something begins
   - beginning, first, outset, get-go [N. Amer], start, kickoff, starting time, showtime, offset
    
2. An academic exercise in which diplomas are conferred
   - commencement exercise, commencement ceremony, graduation, graduation exercise
    
3. The act of starting something
   "he was responsible for the commencement of negotiations";
   - beginning, start

Derived forms: commencements

Type of: change of state, exercise, point, point in time

Encyclopedia: Commencement