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1 definition by odan

 
1.
ガチムチ/がちむち. A Japanese term that literally means "muscular chubby," which refers to big, bulky body types that are very muscular, but also have a good amount of fat.
Jiraiya, Go Fujimoto, and Ebisubashi Seizoh are just a few of the many bara manga artists who specialize in gachimuchi characters.

Many offseason bodybuilders tend to have gachimuchi body types.
by odan August 08, 2012