Odie and Blossom, spend some time and research the American Pit Bull Terrier. Not the dogs that Ceasar Milan or Tia Torres call pitbulls, not the BYB dogs called pitbulls or the dogs the shelters or uninformed vet call pitbulls but rather a pediggreed American Pit Bull Terrier.
This is a small terrier dog. The adult male will be approximately 45 pounds and the female might be around 35 pounds when full grown.
Most of us here realize that the general public call every mixed breed mutt that has any type of bully look a pitbull BUT that doesn't make it true or acceptable.
Any dog without having a legit ped showing it's lineage is a mutt. If you don't know what else to call your dog and people ask, call it what it is, a mutt. It is not a duragatory term. I currently own 2 mutts.