Green’s Dictionary of Slang

black dog n.2

[the most celebrated of such depressions was that suffered by the former prime minister Sir Winston Churchill]

1. a fit of depression or ill humour.

[UK]Thrale Thraliana ii 19 Oct.. 785: The Black Dog is upon his Back; was a common saying some Years ago when a Man was seen troubled with Melancholy [...] Few People however seem to recognize its true Original; which may be found in Dr Henry More's Philosophical Works, where he tells us that Appollonius Tyaneus told the Greeks how that Spirit which was the Scourge of the City where he dwelt [...] appeared to him in Form of a large Black Dog: & leaping on his Back sometimes; filled him with Melancholy for many Days after.
[UK]W. Scott letter 12 May in Lockhart Life (1896) 622/2: A great relief from the black dog which would have worried me at home .
[Ind]Bellew Memoirs of a Griffin II 138: The good-humoured Scotchman [...] presented him with a glass of grog, to allay the fury of the ‘black dog’ as he termed it.
[UK]T. Hughes Tom Brown at Oxford (1880) 371: ‘Yes, sir,’ said the butler, nodding, ‘D.T., sir. After one of his rages the black dog comes, and it’s hawful work; so I hope you’ll go, sir.’.
[UK]R.L. Stevenson New Arabian Nights II 111: He did not seem to be enjoying his luck. The black dog was on his back, as people say, in terrifying nursery metaphor .
[UK]Kipling ‘Black Jack’ in Soldiers Three (1907) 94: I was under the Black Dog — sulkin’ like a child.
[US]Pittsburgh Dispatch (PA) 22 June 12/3: If the black dog of depression has got you by the throat, will not a cheering cup give a peep at the silver lining of the cloud?
[UK](c.1850) G.A. Sala Things I Have Seen I 16: It was not always safe to approach Mr. Thackeray [...] there were seasons when he had, figuratively, speaking, the ‘black dog’ on his shoulder.
[UK]Illus. Police News 24 June 8/4: Then the black dog got on to my back, and stuck there all day.
[US]Number 1500 Life In Sing Sing 2: There’s nothing that eats up the black dog like patience – though possibly you can’t get a pack of cards there.
[US]J.P. Donleavy Ginger Man (1958) 169: Clocklan, I’m suffering from a woeful case of blackdog.
[US]T. Burns Haber ‘Canine Terms Applied to Human Beings’ in AS XL:2 93: black dog. A peevish fit.
[US]R. Price Ladies’ Man (1985) 19: La Donna was in her black dog funk again.
[UK]Observer Rev. 1 Aug. 13: His black dogs are alleviated by brandy, anti-depressants and the recorded speeches of Churchill.
[UK]Roy Jenkins Churchill 427: Such self-destructive pessimism (despite his ‘black dog’ periods of intermittent depression) was not in his nature.
[UK]Ian Sinclair in London: City of Disappearances 123: The upswing of mania. Then the downside: black dog.
[UK]K. Richards Life 204: He would spiral into deep, ominous depressions. Black dogs.
[Aus] A. Savage ‘Killing Peacocks’ in Crime Factory: Hard Labour [ebook] Trev’s great when he doesn’t have the black dog at his heels.
[UK]Times 1 Oct. 🌐 Paxman should have written more about himself and more about his Black Dog. Because where this book touches on his loves, hates and anxieties, it is funny, sad and revealing.

2. delirium tremens.

[UK]‘William Juniper’ True Drunkard’s Delight 247: D.T.s., Delirium tremens, or [...] black dog.

In phrases

walk the black dog on (v.)

(UK prison) to inflict a punishment on a new fellow-prisoner who refuses to pay the automatic fine that is levied on him as a new inmate.

[UK]Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: To Walk the black Dog on any one; a punishment inflicted in the night on a Prisoner, by his comrades, who has not paid his Garnish or Dues.
[UK]Grose Classical Dict. of the Vulgar Tongue (2nd, 3rd edn) n.p.: To walk the black dog on any one; a punishment inflicted in the night on a fresh prisoner, by his comrades, in case of his refusal to pay the usual footing or garnish.
[UK]Lex. Balatronicum.
[UK]Egan Grose’s Classical Dict. of the Vulgar Tongue.