1680s, type of firework, from sky (n.) + rocket (n.2). The verb, in the figurative sense of "to rise abruptly and rapidly" (often with suggestion of 'and then explode and vanish'") is attested from 1895.
prices skyrocketed
skyjack
Skylab
skylark
skylight
skyline
skyrocket
skyscraper
slab
slack
slacken
slacker