[1] : The Collaborative International Dictionary of English v.0.48

valedictorian \val`edicto"rian\, n.
   one who pronounces a valedictory address; especially, in
   american colleges, the student who pronounces the valedictory
   of the graduating class at the annual commencement, usually
   the student who ranks first in scholarship.
   1913 webster

[2] : WordNet (r) 2.0

valedictorian
     n : the student with the best grades who delivers the
         valedictory at graduation syn: valedictory speaker
see also:
valedictory speaker 

Valedictorian >> V Words
Valedictorian, definition of term: Valedictorian
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