Where does "on one's last legs" come from?

Question

To be on one's last legs means to be worn out, tired, run down, and ready to die or otherwise cease working. Some examples I've found are

Grandfather is on his last legs. He'll be on his way to Heaven soon.

I just ran a mile to tell you this; I can't walk up the steps. I'm on my last legs.

My car is on its last legs. I doubt it will get me down the street to the used car dealer.

I've searched a bit on the interwebs, and while definitions abound, I can find no reference to the origin of the phrase. Why "last legs"? What happened to the first ones? What has interchangeable legs anyhow?

Answer 1

To add to @Robusto's answer - regarding the origin - the following seems more definitive and is taken from "The Facts on File dictionary of clichés"

To be extremely tired or about to collapse; near the end. Despite the implication, this term never meant that legs were in any way serial—that is, beginning with the first and ending with the last. Rather, it uses last meaning “near the end” (of one’s energy or life). The expression was already used in the sixteenth century; it appears in the play The Old Law (1599) by Thomas Middleton and Philip Massinger: “My husband goes upon his last hour now—on his last legs, I am sure.” In John Ray’s Proverbs (1678) the term is defined as meaning “bankrupt,” and since then it has been transferred to anything nearing its end or about to fail, as in, “This cliché may be on its last legs.”

However this link dates "The Old Law" as

On his last legs. The Old Law (1618-19), Act v. Sc. 1.

The exact text as it appears online

EUGENIA My husband goes upon his last hour now.

FIRST COURTIER On his last legs, I'm sure.

EUGENIA September the seventeenth, I will not bate an hour on it; and tomorrow His latest hour's expired.

Answer 2

Various sources lists its first usage from the 1590s, and the Google Books result in an etymological dictionary of the Scottish language gives this explanation of the source of the term (screen snap because no C&P available in GB):

Edited to add link to the material, which I forgot earlier.

Also, because of some dialogue in the comments. let me add that last legs does not mean the last of a series of legs, but the last stages of leg strength. It's a metaphorical usage; in fact, legs is used her as a metonym standing in for strength, vitality, or life itself.

Answer 3

I would suggest two possibilities, with little additional evidence other than what is described above, except that which anyone may obtain anecdotally and/or through direct personal observation, as I have.

First, the longer-shot answer, is that I see a recurring theme of bankruptcy, particularly in the older sources. Might it be that, as the term "leg" is used to describe different stages of trades in finance, the word might first have been used to describe different tranches of loans? A last leg, then, might be like a 2nd,3rd or even later mortgage on a business or farm lands? Or, if one were paying an arm and a leg on interest, or selling off assets to pay one's debts, then it would be a very bad thing to be down to one's last legs (having sold off the arms already). I would suggest focusing research into the use of the term "legs" in conjunction with loans/lending/banking in the 1600s, and see what comes up.

The more likely answer, though, seems the simpler and far more ancient. The millipede answer may be the closest to the truth stated thus far. even if it is somewhat exaggerated, intentionally comical and not fully accurate, considering the organism's capability for regeneration. I would argue that the phrase actually refers to a typical 6-legged insect or 8-legged arachnid. I've crushed more than a few in my day, in my rural youth and military young-adulthood (I likely experienced the need to do battle with many-legged opponents almost as often as the average person living in the 1600s and prior would have, unlike many modern urbanites and academics who may be less familiar with the pathetic visage portrayed by a once-6-legged creature that has been reduced to 2 or 3). Indeed, the most common outcome when stepping on or swatting a many-legged pest, short of instant death, is a half-dead, still moving, mangled bug, which is almost always missing several of its legs. The same is true of an insect or spider that narrowly escapes attack by a predator or a competing species. Therefore, I suspect the phrase is literal, and does refer to a serial numbers of legs. The idiom makes far more sense if the original subject of the metaphor starts out with 6-8 legs, rather than 2.

Answer 4

To be on one's last legs is a well known idiom. There is an entry for it in the OED divided into two parts. The first (a) concerns humans or legged animals - meaning they are literally close to death. The second is a figurative sense applying the principal to something material, such as a car or a machine, or abstract such a policy or a theory.

It is related to an idea of legs as less than literal, more to the benefit or power of legs. For example a football manager may introduce a substitute in the later stage of a match to give the team "fresh legs".

on (also †upon) one's last legs. Formerly also †to one's last legs, †near one's last legs (obsolete).

(a) At or near the end of one's life; close to death.

In quot. 1614 as part of an extended metaphor.

1614 I. T. Horrible Creuel & Bloudy Murther sig. A4 The doating World limping on hir last legges.

a1627 T. Middleton & W. Rowley Old Law (1656) v. 59 Eug. My husband goes upon his last houre now. 1. Cour. On his last legs I am sure.

1671 J. Dryden Evening's Love ii. 25 He had brought me to my last legs.

1764 S. Foote Mayor of Garret ii. 43 You was pretty near your last legs.

1798 C. Stearns Maid of Groves ii. iv. 207 Fayther's on his last legs—He has had another right snap of the gout.

1870 L. M. Alcott Let. 11 Aug. in E. D. Cheney L. M. Alcott (1889) ix. 245 The Emperor is on his last legs in every way. He is sick..and so nervous he can't command the army as he wanted to.

1974 W. Foley Child in Forest 73 'Im do only come to see if I be on me last legs.

2005 B. Keating & S. Keating Blood Sisters (2006) xxvii. 514 He's in hospital in Nairobi. On his last legs, poor man.

(b) figurative. On the brink of ruin or collapse; almost completely worn out or >spent as a force.

1678 J. Ray Coll. Eng. Prov. (ed. 2) 89 A Bankrupt... He goes on's last legs.

1753 Pædo-baptism ii. 37 As his conclusion is now come to it's last legs; so it will be hard set, to maintain it's ground.

1846 T. De Quincey Syst. Heavens in Tait's Edinb. Mag. Sept. 569/1
If the Earth were on her last legs.

1895 Sunday Herald (Syracuse, N.Y.) 13 Jan. 11/5 Members wish to refute the assertions..that Hayes council ‘is on its last legs’. Never in the history of the council was it in better shape.

1952 Good Housek. (U.S. ed.) Dec. 102/2 All her sheets and pillowcases were on their last legs, and most of the New York stores were having August White Sales.

2003 B. Trapido Frankie & Stankie vii. 138 The green buses are always on their last legs, belching out streams of black smoke and overloaded with downtown workers.

Answer 5

The above quotes explain the meaning and that you can find in any dictionary. But they don't try to find out out where this funny picture comes from. And I dare to say you won't find such an explanation.

I have the habit simply to ask can I find a situation or a model where the expression might make sense. And any situation or model that would make sense is acceptable.

My personal model is conected with some insects with six legs which are fighting. They try to bite off the legs of each other. The weakest one has already four legs bitten off and can hardly move. Here you can say it's on its last legs and its end is predictable.