When someone sees someone else's incredibly cute dog and uses any combination of the following noises or utterances such as; ohh, awwwww, ahh and higher pitched ohhhh. This is usually followed by an exlmation of "Oh how cute!" "Can I hold you?" "I want one," and "I love you!"
A girl walks by a cute puppy dog in a car window and says "Awwwwww, Ohhhh, He's so cute! She goes on and on and then shudders a little, thus having a dogasm.
Every dog has a spot on their body, that when pet or rubbed, causes one of their hind legs to flutter back and forth.
(While I rub behind my dog's right ear.) Honey, look at Harleigh, she's having a dogasm.
The look on a dog's face when a scratch given by a person is so intense it's leg begins to spasm.
My god Fido's having one hell of a dogasm.
An overly enthusiastic display of affection by a dog toward its owner or another person
Every time we come home from work, Rusty has a dogasm all over the furniture, floor, and our pants.
The orgasm of a dog.
"... sort of snacking back and forth with his mouth open and his pink tongue whipping around in an ecstatic dogasm."
(Quotation from "The Stupidest Angel" by Christopher Moore)