Legal definition of a rifle

[LLF]

With regard to Massachusetts law, is there a legal definition for the overall length of what is considered a rifle in Massachusetts?
I know the barrel must be at least 16".
Thank you.

 

[MisterHappy]

AFAIK, "rifle" is not defined, except that it's not a "firearm" (i.e. handgun)

There are federal regs as to length.