orgiastic

adjective

1. of, relating to, or having the nature of an orgy.
2. tending to arouse or excite unrestrained emotion: orgiastic rhythms.
3. Sociology. (of an expressive crowd) reaching a peak of emotional intensity, often of an ecstatic nature and frequently expressed by uninhibited behavior.

adj.1690s, from Greek orgiastikos “fit for orgies, exciting,” from orgiastes “one who celebrates orgies,” from orgiazein “to celebrate orgies,” from orgia (see orgy).