Definition & Meaning of "gammy"in English

What does "gammy" mean in British slang?

The structure is a simple adjective of uncertain origin, possibly from Old Norse "gammr" (bad, ugly) or dialectal English "gammy" meaning lame or crooked. It is used in British English, particularly in the Midlands and Northern England, to mean injured, sore, or not functioning properly, especially referring to a leg or limb. People typically say "I've got a gammy leg" or "His knee went gammy after the fall."