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1.
Hemorrhoid suppositories shaped like a rocket designed to relieve the symptoms of piles in the rectum.

The Fonny Rocket is a special suppository designed to heal hemorrhoids in 3 days or less.
Fonny Rocket does not get lost in the rectum but stays comfortably in place for many hours to soothe and heal inflamed tissue.
by Ezmerelda Berger March 24, 2013
28 1
 
2.
A nickname for a person or given to someone who is deemed by their group of friends as high energy, highly funny, highly entertaining and at times, high maintenence. This word is also used as a metaphor to describe the act or action of, going off like a rocket. Going off like a rocket is also a reference to the Launch of a Rocket. Fonny is a acronym for funny. Hense, FONNY ROCKET. FONNY ROCKET is also the name of a fire cracker.
Hey check out the dance floor, there's that FONNY ROCKET, f#@k she's funny, look at her go off like a ROCKET.
by FONNY ROCKET September 01, 2008
8 32