I. ˈrȯi-stər noun
Etymology: Middle French rustre lout, alteration of ruste, from ruste, adjective, rude, rough, from Latin rusticus rural — more at rustic
Date: 1551
archaic : one that roisters : roisterer
II. intransitive verb
( rois·tered ; rois·ter·ing -st(ə-)riŋ)
Date: 1582
: to engage in noisy revelry : carouse
• rois·ter·er -stər-ər noun
• rois·ter·ous -st(ə-)rəs adjective
• rois·ter·ous·ly adverb