Like Faggot only less severe and more silly or sarcastic.

Origin:

A very common typo, often since the 's' key is so close to the 'a' key on keyboard.
"Oi! Fasgat! Gimmie a beer, will ya?"

"I threw my back out humping your mom's friend lastnight man, it would have been awesome if your fasgat brother hadn't told me to backoff though"
by Gabriele Gabba August 21, 2007
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