The phrase "little rocket" refers to something small that has the ability to move quickly and with power, similar to a small rocket in outer space. Full definition
Looking over this cute little rocket ship makes me wonder what could have been. (automobilemag.com)
Great stuff, we went ahead and had a nice push down there into the lunch hour in the stock index futures and then we had a nice little rocket ship back up. (robhoffmantrader.com)
Who doesn't love to make a fun little rocket to entertain yourself on a sunny day outside? (inourhappyplace.com)