val ‧ e ‧ dic ‧ to ‧ ri ‧ an /ˌvælədɪkˈtɔːriən, ˌvælɪdɪkˈtɔːriən/ BrE AmE noun [countable] American English
the student who has received the best marks all the way through school, and who usually makes a speech at the ↑ graduation ceremony
val ‧ e ‧ dic ‧ to ‧ ri ‧ an /ˌvælədɪkˈtɔːriən, ˌvælɪdɪkˈtɔːriən/ BrE AmE noun [countable] American English
the student who has received the best marks all the way through school, and who usually makes a speech at the ↑ graduation ceremony
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012