Used in a manner to describe dislike or anger. In order to properly administer the "bad dog" verbiage one must first make a hand gustier like you are pinching or picking something up using your thumb and index fingers with the middle, ring, and pinky fingers extended and making a shaking motion from right to left like you are shaking something and make the statement BAD DOG! (Hand Gustier is optional)
**You just saw a very heavy person in a less than attractive speedo or you kid just knocked over a glass of water, or you saw something that was really bad**
"Dude wearing that speedo when your 5,000 pounds thats a BAD DOG"
"That song was a bad dog"
"Oh Bad Dog..."
"I just cut my damn hand, Bad Dog"
*your friend just cut one "Dude...Bad Dog"
"He fucked her, bad dog"