n. 1 cylindrical firework or signal etc. propelled to a great height after ignition. 2 engine operating on the same principle, providing thrust but not dependent on air intake. 3 rocketpropelled missile, spacecraft, etc. 4 slang severe reprimand. (t)1 a move rapidly upwards or away. b increase rapidly (prices rocketed). 2 bombard with rockets. [French roquette from Italian]