Cutaway

From GuitarWiki

A cutaway is a part of the body that's been removed so it's easier to reach the fingerboard's top notes. Most electric guitars have at least one cutaway. Some have two (one on each side of the neck). Acoustic guitars don't feature cutaways as often as electric guitars, since cutting away from the body affects its tone, plus the body is so deep, from front to back, that it often doesn't make it much easier to play high on the neck.