Bun in Jamaica means infedility. So when you are unfaithful to your mate, it is said "Yu gi dem bun". Download from amazon.com, Joan Williams'6th editionof "The "Original Dancehall Dictionary" and you will become familiar with the popular and expressive Jamaican language.
This means they want their burger on a bun.
If you mean slang as in internet slang, then it means "Certified Old Fart".
Prego Bun in the oven knocked up in troublepreggers{ prego means "your welcome " in Italian} in the family way
Pregnant. Slang terms include bun in the oven, preggers, up the duff, expecting.
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"bun"
I have no idea what you mean by this question.
Garrett mean in cockney slang
Slang is slang It's the s' "LANG " uage.
In old slang, milkshake mean butt.
Cool itself, unless you are using it to mean mildly cold, is a slang word. Just because it is old slang doesn't mean that it is not still slang.