Definition of formal :
1. Belonging to the constitution of a thing, as distinguished from the matter composing it; having the power of making a thing what it is; constituent; essential; pertaining to or depending on the forms, so called, of the human intellect.
2. Belonging to the form, shape, frame, external appearance, or organization of a thing.
3. Dependent in form; conventional.
4. Devoted to, or done in accordance with, forms or rules; punctilious; regular; orderly; methodical; of a prescribed form; exact; prim; stiff; ceremonious; as, a man formal in his dress, his gait, his conversation.
5. Done in due form, or with solemnity; according to regular method; not incidental, sudden or irregular; express; as, he gave his formal consent.
6. Having the form or appearance without the substance or essence; external; as, formal duty; formal worship; formal courtesy, etc.
7. See Methylal.
8. Sound; normal.
directed, noble, chunk, dignified, nonrepresentational, ballock, ceremonial, starchy, white-tie, polite, clod, musket ball, semi-formal, punctilious, social, orchis, dressed up, precise, logical, orderly, lawful, baronial, dinner dress, bollock, form-only, semiformal, dressy, symmetrical, elegant, evening gown, full-dress, dinner gown, lump, approved, pro forma, ceremonious, glob, set, stiff, nut, buckram, nominal, schematic, egg, ritual, legal, black-tie, ritualistic, reserved, clump, testis, stately, imposing, testicle, literary, distant, prescribed, statuesque, titular, established, ball, official, dress, plain, courtesy, liturgical, confirmed, courtly, orb, perfunctory, globe, positive
conforming (part of speech: adjective)
ostentatious (part of speech: adjective)
flourishing, histrionic, flagrant, snazzy, flashy, gaudy, boastful, opulent, exhibitionistic, vain, affected, garish, dashing, dramatic, splashy, rakish, forced, stilted, grandiose, ostentatious, fussy, pompous, grandiloquent, blatant, flaunting, flamboyant, sensational, shameless, ornate, jaunty, showy
- Promise me there shall be no formal engagement, and I will let him come now and then." - "Put Yourself in His Place", Charles Reade.
- In a formal letter. - "Man and Wife", Wilkie Collins.
- Even at the moment of formal welcome he must have felt that trouble was in store. - "The Fighting Governor A Chronicle of Frontenac", Charles W. Colby Edited by George M. Wrong and H. H. Langton.