BUOYANT
buoyant, chirpy, perky
(adjective) characterized by liveliness and lightheartedness; “buoyant spirits”; “his quick wit and chirpy humor”; “looking bright and well and chirpy”; “a perky little widow in her 70s”
buoyant, floaty
(adjective) tending to float on a liquid or rise in air or gas; “buoyant balloons”; “buoyant balsawood boats”; “a floaty scarf”
Source: WordNet® 3.1
Etymology
Adjective
buoyant (comparative more buoyant, superlative most buoyant)
Having buoyancy; able to float.
(figuratively) Lighthearted and lively.
Source: Wiktionary
Buoy"ant, a. Etym: [From Buoy, v. t. & i.]
1. Having the quality of rising or floating in a fluid; tending to
rise or float; as, iron is buoyant in mercury. "Buoyant on the
flood." Pope.
2. Bearing up, as a fluid; sustaining another body by being
specifically heavier.
The water under me was buoyant. Dryden.
3. Light-hearted; vivacious; cheerful; as, a buoyant disposition;
buoyant spirits.
– Buoy"ant*ly, adv.
Source: Webster’s Unabridged Dictionary 1913 Edition