The Collaborative International Dictionary of English v.0.48:

skyrocket \sky"rock`et\ (sk[imac]"r[o^]k`[e^]t), v. i.
   To rise rapidly; -- usually used figuratively, as of prices.
   [PJC]

The Collaborative International Dictionary of English v.0.48:

skyrocket \sky"rock`et\ (sk[imac]"r[o^]k`[e^]t), n.
   A rocket that ascends high and burns as it flies; a species
   of fireworks.
   [1913 Webster]

WordNet (r) 3.0 (2006):

skyrocket
    n 1: propels bright light high in the sky, or used to propel a
         lifesaving line or harpoon [syn: rocket, skyrocket]
    2: sends a firework display high into the sky [syn: skyrocket,
       rocket]
    v 1: shoot up abruptly, like a rocket; "prices skyrocketed"
         [syn: rocket, skyrocket]