The Oxford Thesaurus An A-Z Dictionary of Synonyms - effervescentn.

1) bubbling, fizzy, carbonated, sparkling, fizzing, gassy; foaming, foamy, frothing, frothy, bubbly: I prefer effervescent mineral water to still. 2) bubbling, bubbly, high-spirited, vivacious, ebullient, lively, exuberant, buoyant, animated, lively, exhilarated, excited, enthusiastic, irrepressible: Jeanette's effervescent personality endeared her to everyone who met her. EFFICACIOUS adj. effective, effectual, productive, competent, successful, efficient, useful, serviceable; capable: He was not very efficacious in getting the council to change their policy.