Green’s Dictionary of Slang

1. wonderful, excellent, first-rate.

1845		J. Lindridge Sixteen-String Jack 125: Bravo! Bravissimo! I call it phizzing, I do, and show me the man who dare deny it?
1850		‘Epistle from Joe Muggins’s Dog’ in Era (London) 26 May 3/4: Both Mildew and Nigger have had fizzin trials.
1855		(con. 1850) Fights for the Championship 219: It was ‘phizzing’ hot throughout the day.
1864		London Standard 13 Dec. 3/3: Among the words that fast society has borrowed [...] Fizzing, first-rate, or splendid.
1873		Sl. Dict.
1903		Truth (London) 18 June 1678/3: Slang terms: [...] fizzing, loud, nobby, no-flies, O.K., out-and-out, pick-me-up, pink, posted-up [etc] .
1913		C. Mackenzie Sinister Street I 166: I think that girl was simply fizzing.
1940		M. Marples Public School Slang 5: Words expressing general approval [...] fizzing (1885) : perhaps implying speed, like rattling, ripping.
1958		Willans & Searle Complete Molesworth (1985) 370: She is absolutely fizzing more lovely ever than prudence entwistle the under matron.

2. a general negative; also as adv. [euph. for fucking adj. (1)].

1913		Sport (Adelaide) 22 Mar. 12/4: [of a person] They Say [...] That Fred O, the dizzy limit, is not going to play football this year, because he says it’s too fizzing rough.
1958		J. Arden Live Like Pigs Act II: Oh go to hell, you and your fizzing husband.
1995		P. O’Keeffe Down Cobbled Streets, A Liberties Childhood 61: I wish they’d fizzin’ well make up their minds.