The Oxford Thesaurus An A-Z Dictionary of Synonyms - formality n.

1) Often, the formalities. form, convention, conventionality, practice, procedure, custom, wont, observance, protocol, ceremony, rite, ritual: Observe the legal formalities by having this document witnessed. Formality requires that you walk backwards out of the room. 2) strictness, punctilio, exactness, precision, correctness, rigidity, stiffness, inflexibility: We must maintain the formality of Sunday service. 3) etiquette, politesse, decorum, punctilio, conformity, propriety: Formality prohibits casual conversation.