What it means
Used for anything that's a bit wrecked or unreliable, especially a body part. A gammy leg or eye is injured, stiff, or just not right. You can also call tech or a plan gammy when it's acting up and making everything more hassle than it should be. Not totally broken, just barely hanging on.
Usage examples
"Was meant to go for five-a-side, but me gammy knee's at me again, so I'm hobbling round the gaff and skipping the match."
"I cannot do the hike with this gammy knee, it gives out every time I go downhill for more than ten minutes."
Where it comes from
Most likely from game leg, an old dialect way of saying a lame or injured limb, worn down over time into gammy. Now it covers any body part that is playing up, a gammy knee, a gammy eye, and by extension anything dodgy or unreliable. Very Irish and British, said with a wince and a shrug.
Other ways to say it
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