WordNet (r) 3.0 (2006):

rite of passage
    n 1: a ritual performed in some cultures at times when an
         individual changes status (as from adolescence to
         adulthood)

Moby Thesaurus II by Grady Ward, 1.0:

29 Moby Thesaurus words for "rite of passage":
   baccalaureate service, celebration, ceremonial, ceremony,
   commencement, convocation, empty formality, exercise, exercises,
   formal, formality, function, graduation, graduation exercises,
   inaugural, inauguration, initiation, liturgy, mummery, observance,
   office, performance, religious ceremony, rite, rite de passage,
   ritual, service, solemnity, solemnization