Aside from the fact it is one of those necessary items to walk with, and the fact we can have two or four for most humans and animals, there are a few other uses for the word ‘leg’.
‘You haven’t got a leg to stand on’, doesn’t necessarily mean you have no legs, but that you are in a precarious position.
“the table had ornate legs’, yes, even non-living objects can have legs, like tables and chairs.
“It was the fifth leg of the race’, meaning it can be a stage of a race.
“He was legless’, meaning that he was too drunk to stand up. Some might think being legless is a badge of honour, but I suspect those people have been drinking a long time and the alcohol has destroyed most of their brain cells.
“leg it!’, meaning get the hell out of here before you’re caught.
Then, finally, ‘he’s on his last legs’, meaning that he’s exhausted, or about to die.
I’m sure there’s more but that’ll do for now.
I have to use my legs to get some exercise, of which the first leg is to the tripod to check if its legs are stable, and the second leg is to come back to the table and replace one of the legs which is broken. Then I’ll leg it to the pub where hopefully I won’t become legless.