Green’s Dictionary of Slang

1. absolute, complete; esp. in phrs. blithering idiot, blithering fool etc.

1878		Greenville Times (MS) 13 July 4/1: I dread [...] the cunning and cruel catamount cast. / That tokens the blithering blistering cast of that old fat Butler’s eye.
1885		Salt lake Herald (UT) 26 Apr. 7/2: What a powerful lot of blithering idiots this future race would be to entertain such a notion.
1894		Lincs. Echo 15 Nov. 3/2: The gentleman [...] who had described the Board of Agriculture as a ‘lot of blithering idiots’ was not far wrong.
1898		W. Pett Ridge Mord Em’ly 109: As for us [...] we’re what we may term a lot of blithering machines; nothing more nor less; we go on, and on, and on, and one day’s jest like another.
1900		‘Doss Chiderdoss’ ‘Experimental’, Sporting Times 10 Feb. 1/4: It will turn out a failure, a blithering hash!
1900		Indian Advocate (Sacred Heart, OK) 1 Dec. 30: ‘Is there a blithering idiot at the end of this phone?’ [...] ‘Not at this end, sir’.
1902		Eve. Post (NZ) Supp. 27 Dec. 1/3: The great man was requested to ‘hold his tongue for a bletherin’ idiot’.
1904		Sun. Times (Perth) 6 Mar. 5/4: Talking blithering rot to a handful of supporters.
1906		Marvel 27 Oct. 391: I’m a blithering idiot!
1910		Sun. Times (Perth) 13 Feb. 2nd sect. 1/4: That assembly of blithering asses known as the Cotteslowe Municipal Council.
1915		E. Pound letter 17 May in Paige (1971) 60: He hogs a minor job which would be a living to some other man, but which wouldn’t pay for the gasoline in S----’s automobile. Blithering sow.
1915		‘Sapper’ Michael Cassidy 110: ‘You blithering ass’.
1920		Ade Hand-made Fables 95: Some day he would bust forth from his blithering Bondage and jamboree his way through Europe.
1927		N.Z. Truth 29 Dec. 4/6: Don’t be a blithering idiot. Come off that talk, now.
1937		A. Christie Dumb Witness (1949) 171: What a blithering fool I am!
1941		P.C. Wren Odd – But Even So 22: You blithering son of a sow.
1955		K. Williams Diaries 9 Sept. 117: Well of course it’s all the most blithering rubbish I’ve ever had to appear in.
1961		‘Frank Richards’ Billy Bunter at Butlins 119: You blithering bloater, he would be half a mile away with your wallet by this time.
1978		(con. 1940s) J.G. Farrell Singapore Grip 151: God help ye, y’ blithering lot o’ helpless bastards!

2. nonsensical, babbling, foolish.

1934		Wodehouse Right Ho, Jeeves 21: Of all the dashed silly, drivelling ideas I ever heard [...] this is the most blithering and futile.
1938		X. Herbert Capricornia (1939) 444: Norman felt sure that everyone but the drunken blithering Tocky was sneering at him.
1981		B. Hoy ‘Uncle George’ in Wright Cockney Dial. and Sl. (1981) 108: Yer couldn’t afford to be choosy, / Yer’d work till you dropped for a quid / For yer trouble an’ strife / And to keep bref o’ life / In a blitherin’ young saucepan-lid.
1999		Guardian Rev. 17 Sept. 5: Populated by blithering officers, stroppy cockneys [...] cliches of every sort.
2000		Guardian Guide 22–28 Jan. 61: An eccentric, maverick detective [...] and a blithering companion.