GAS

GAS is a commonly used acronym to describe someone who is unfaithful. More specifically unfaithful in a long term relationship (> 5 years)

The term is sometimes used as a greeting in some circles.

Abraham - “Mush, just found out my lass has been cheating on me for 20 months with some dingwhop from her work”

Ariana - “She’s a total GAS mate”