adjective
1.
conducted or carried out without rigidly prescribed procedure
carried on an informal investigation
Synonyms: irregular, unceremonious, unofficial
Related Word: casual, spontaneous; unauthorized; unconventional; private, special
Contrasted words: authorized, ceremonious, conventional, official, regular
Antonyms: formal
2.
Synonyms: easygoing 3, breezy, casual, ||common, dégagé, low-pressure, relaxed, ||sonsy, unconstrained, unfussy
Related Word: familiar, natural, simple
Contrasted words: affected, mannered, prim, rigid, stiff, stilted
Antonyms: formal