1. able to float
1. Even if it flips over, a rowboat will remain buoyant.
2. cheerful and optimistic
2. Her mood is naturally buoyant, even when she is facing difficulties in her life.
blithe, buoyant, ebullient, jocular
despondent, dour, lugubrious, maudlin, morose, saturnine
buoyant = Boy + ant when a boy feels like an ant, which is very light, he feels very light and lively.