Synonyms for Ceremonious (same or very similar meaning)
WordNet sense 1 (characterized by pomp and ceremony and stately display):
pompousWordNet sense 2 (rigidly formal or bound by convention):
conventionalWordNet sense 3 (being in accord with established forms and conventions and requirements (as e.g. of formal dress)):
formalFrom the ODE community, based on WordNetadd/edit