Search Result for "teach-in": 
Wordnet 3.0

NOUN (1)

1. an extended session (as on a college campus) for lectures and discussion on an important and usually controversial issue; 



WordNet (r) 3.0 (2006):

teach-in
    n 1: an extended session (as on a college campus) for lectures
         and discussion on an important and usually controversial
         issue