Those of Germanic descent might know the word snit as a noun meaning "an apple slice," but this doesn't help etymologists much. In fact, it just gets them into a "snit" (a "state of agitation"). No matter how they slice and dice the word snitty, they can't get to its core. All we know is that "snit" was being used as early as 1939 and "snitty" appeared some 40 years later, and that both words are mainly used in the United States.