"Bayazid drew Donald into wild revels, plied him with strong drink and even as he roared and roystered, he keenly watched the Highlander."
—Lord of Samarcand
intr.v. rois·tered, rois·ter·ing, rois·ters
1. To engage in boisterous merrymaking; revel noisily.
2. To behave in a blustering manner; swagger.
[From obsolete roister, roisterer, probably from Old French rustre, ruffian, alteration of ruste, from Latin rūsticus, rustic; see rustic.]