Sibilant1. (a.) Making a hissing sound; hissing; as, s, z, sh, and zh, are sibilant elementary sounds.
2. (n.) A sibiliant letter.
Thesaurus Entries
active, activist, activistic, agog, airy, alive, animated, aquiver, aroused, atingle, atwitter, beaten, blebby, blistered, blistering, blistery, boiling, bouncing, bouncy, brash, breezy, brisk, bubbling, bubbly, buoyant, burbling, burbly, bursting, carbonated, carried away, chiffon, chipper, ebullient, energetic, enthusiastic, excited, exhilarated, expansive, exuberant, fired, fizzing, fizzling, fizzy, foaming, foamy, frisky, frothing, frothy, full of go, full of life, full of pep, gassy, gay, gleeful, high, high-spirited, hilarious, hissing, hopped up, hushing, impassioned, inflamed, irrepressible, jolly, keyed up, lathered up, live, lively, manic, mercurial, militant, mirthful, moved, peppy, perky, pert, puffed, quicksilver, ready to burst, resilient, roused, sibilant, sissing, sizzling, smacking, snappy, sniffing, sniffling, snoring, snuffling, souffle, souffleed, spanking, sparkling, spirited, sprightly, spry, spumescent, steamed up, stimulated, stirred, stirred up, thrilled, tingling, tingly, turned-on, vesicant, vesicated, vesicatory, vesicular, vivacious, volatile, wheezing, wheezy, whipped, whipped up, worked up, wrought up, yeasty, zingy