Synonyms for formal

noun a lavish dance requiring formal attire

noun a gown for evening wear

adjective being in accord with established forms and conventions and requirements (as e.g. of formal dress)

adjective characteristic of or befitting a person in authority

adjective (of spoken and written language) adhering to traditional standards of correctness and without casual, contracted, and colloquial forms

adjective represented in simplified or symbolic form

adjective logically deductive

adjective refined or imposing in manner or appearance; befitting a royal court