"quick, energetic," 1825, from snap (v.) + -y (2). Meaning "clever, smart" is from 1871; that of "neat and stylishly elegant" is from 1881. Related: Snappily; snappiness. Command make it snappy attested from 1910.
snappy conversation
snappy weather
a snappy pace
snap
snapdragon
snape
snapper
snappish
snappy
snapshot
snare
snarf
snark
snarky