buoyancy vs sprightliness

buoyancy and sprightliness both are nouns.

Word	Noun	Adjective	Verb	Adverb
buoyancy	Yes	No	No	No
sprightliness	Yes	No	No	No

As nouns, sprightliness is a hypernym of buoyancy; that is, sprightliness is a word with a broader meaning than buoyancy:

Other hypernyms of buoyancy include life, liveliness, spirit.

buoyancy (noun)	sprightliness (noun)
the property of something weightless and insubstantial	animation and energy in action or expression
irrepressible liveliness and good spirit
the tendency to float in water or other liquid
cheerfulness that bubbles to the surface