Gyatt or gyat is a slang term that is used to express strong excitement, surprise, or admiration. Gyatt is most commonly used as an exclamation in reaction to seeing a large butt (that is, the buttocks) and may be used as a noun to mean a large butt.
For example, If a person is having a too big butt so this slang can be used as “You have level 10 Gyatt” Levels can be decided by you yourself though by understanding how big the butt is.