on one's last legs

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on one's last legs

1. (idiomatic) About to die.
   • 1824, Sir Walter Scott, chapter 6, in St. Ronan's Well:

     [A] friend who assists me with a view to future profit . . . lies like the fox's scent when on his last legs, increasing every moment.

   • 1913, Jack London, chapter 6, in The Valley of the Moon:

     He is on his last legs. His kidneys are 'most gone. Remember, 'tis I must bury him.

2. (idiomatic, by extension) About to lose viability or become defunct.

   My computer's on its last legs; it crashes running Minesweeper.

   • 1905, Robert Louis Stevenson, “The Beach of Falesa”, in Island Nights' Entertainments:

     [T]he wood was main dark, but had a kind of a low glow in it like a fire on its last legs.

• not have a leg to stand on
• have seen one's last gum tree