Adjective informal has 4 senses
- informal - not formal; "conservative people unaccustomed to informal dress"; "an informal free-and-easy manner"; "an informal gathering of friends"
Antonyms: formal, ceremonial, ceremonious, conventional, form-only, full-dress, dress, nominal, titular, positive, prescribed, semiformal, semi-formal, black-tie, starchy, stiff, buckram, white-tie, pro forma, perfunctory
- informal, loose - not officially recognized or controlled; "an informal agreement"; "a loose organization of the local farmers"
Antonym: official (indirect, via unofficial)
- informal - used of spoken and written language
Antonyms: formal, literary
- cozy, intimate, informal - having or fostering a warm or friendly atmosphere; especially through smallness and informality; "had a cozy chat"; "a relaxed informal manner"; "an intimate cocktail lounge"; "the small room was cozy and intimate"
Antonym: unfriendly (indirect, via friendly)
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