The phrase "get off your duff" is a call to action. The recipient of this exhortation is (literally or figuratively) sitting, unmoving, and is being asked to get off of his buttocks, as seen in Entry 2.

Definition of duff

(Entry 1 of 3) 1: a boiled or steamed pudding often containing dried fruit

2: the partly decayed organic matter on the forest floor

3: fine coal : SLACK duff

(Entry 2 of 3) : BUTTOCKS get off your duff

(Entry 3 of 3) British : INFERIOR, WORTHLESS

(Source: Merriam-Webster) The same site lists the etymology:

History and Etymology for duff

Noun (1) English dialect, alteration of dough

Noun (2) origin unknown

Adjective duff, noun, something worthless, from DUFF entry 1

The Online Etymology Dictionary agrees:

"buttocks, rump," 1830s, of unknown origin. The word had a variety of colloquial, slang, or provincial senses late 18c.-early 19c., some of them at least probably related: "dough," also "stiff flour pudding" (nautical, 1840); something worthless or spurious (1781).


This site has a discussion of the BE phrase up the duff. The accepted answer says that the OED says it is of Australian origin, and is a slang phrase for being pregnant. (BE speakers may recognize the pudding club and AE speakers would recognize a bun in the oven as euphemisms for pregnancy; this would fit well with Entry 1.)

A folk etymology could stab at dough or pudding referring to buttocks. Perhaps:

  • The resting person is torpid from eating sweet pudding.
  • The buttocks are associated with dough, either through shape or over-consumption.
  • The buttocks are associated with inferiority or worthlessness.

And a folk etymology for the association with pregnancy:

  • She is avoiding strenuous labor because of her bun in the oven by resting on her backside.

But these seem forced.

How did duff come to mean buttocks?

  • This expression was unknown to me (UK), although Lexico is the only online dictionary to label it as American. Commented Mar 5, 2021 at 13:20
  • I heard it in a US sermon last week. It was a bowdlerized version of "Get off your ass" and felt a little dated like "get off your keister." The latter does have an etymology at zippyfacts.com/… . Here an immigrant's strongbox (keiste) is sat upon, and the strongbox and buttocks are conflated.
    – rajah9
    Commented Mar 7, 2021 at 12:39
  • I'd guess that 'duff' is simply a minced version of 'butt' - similar pattern, same vowel, similar to dang, frick, shucks, cheese and rice, goldurn, etc etc etc. The way to evaluate such a claim is by plausibility as is the case with any phonological rule even though the latter is much more concrete.
    – Mitch
    Commented Apr 4, 2021 at 14:56
  • @KateBunting Mitch suggests, and I tend to agree with him, that 'duff' is a minced version of 'butt'. Since we have only adopted 'butt' as a word for 'buttocks' recently there was no real need for us to adopt the minced version as well.
    – BoldBen
    Commented Jun 25, 2021 at 3:54
  • 1
    I would hazard a guess that this might involve a kind of reversed Cockneyfication ( plum duff = plum = rhymes with bum (=arse).
    – user46359
    Commented Dec 27, 2021 at 11:16

2 Answers 2


The Phrase Finder cites the OED and suggests that it might be related to a particular dough-pudding made from flour boiled in a bag, from which probably the idea of ass, or buttocks:

Duff has been used to mean buttocks, backside, ass, from no later than 1837 and probably much earlier. The OED offers the suggestion that it might be related to a particular dough-pudding, that is:

  • "a. Dough, paste. (dial.) b. A flour pudding boiled in a bag.; a dumpling." In parts of northern England dough is, or was, pronounced duff, to rhyme with enough.

The site wordreference.com suggests that:

Duff, as a slang term for buttocks, dates back to the mid-19th century. It originated in Scotland, and could be related to doup, another Scottish word for buttocks. The pudding sense is also from Scotland, and is a dialectal variation of dough.

  • The entry at Phrase Finder says "Duff has been used to mean buttocks." I'm still at a loss how that association was made. Was pudding in a bag reminiscent of butt cheeks in the 1800s? Without further evidence, it seems like a folk etymology.
    – rajah9
    Commented Mar 5, 2021 at 17:21
  • @rajah9 - I think the origin is not known, and as it often happens you have to go with a few reasonable assumptions. The Scottish trail is interesting though.
    – user 66974
    Commented Mar 5, 2021 at 17:42
  • @rajah9, given the attested connection both to "dough" (i.e. cooking dough), and to "worthless or inferior" things, it isn't a huge leap of imagination to see connections to the buttocks. Bear in mind also that people in that era also used to sleep on and under sacks of bulk product (see for example the history of "chimney sweep carcinoma"), and probably often used sacks of bulk product for sitting as well, so it becomes associated in the same way as "mitts" becomes a slang word for the hands as well as for the gloves that cover them, for example.
    – Steve
    Commented Apr 4, 2021 at 15:47
  • @Steve Very interesting, and not an association that I had made before. This could be a fourth folk etymology, so do you have some references that you might post in your own answer?
    – rajah9
    Commented Apr 4, 2021 at 16:13

I am not 100% on this answer but, as I see no one has responded, I will give you the meaning I have always understood.

"Get off your duff".
'A soldier carries a duffle bag. Another soldier sees him sitting on his duffle bag. They are both waiting on a train. As the train pulls up, the standing soldier turns to the soldier still sitting on his duffle bag and says, "Get off you duff, the train's here."'

The standing soldier may or maybe not be annoyed. It's just the slang talk between the soldiers.

Hope this helps.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.