Green’s Dictionary of Slang

1. very strong; intense.

1908		Bulletin (Sydney) 10 Dec. 25/4: There wuz me, drivin’ along under a broilin’ sun, with a dynamite thirst, an’ twelve beautiful bottles in the cart.
1935		O.O. McIntyre New York Day by Day 11 June [synd. col.] My choice for the dynamite drink is the absinthe drip.
1943		J. Binning Target Area 30: ‘This may be dynamite, baby,’ he said, as he gingerly cut at the string holding one cork. [...] The cork flew off like a bullet.
1976		M. Arble Long Tunnel 150: We had some dynamite THC last week.
1987		in Delacoste & Alexander Sex Work (1988) 67: I’ve got some dynamite speed [...] really good stuff.

2. excellent, wonderful, first-rate; often as excl. dynamite! wonderful!

1915		Drew & Evans Grafter (1922) 1: [of betting, very attractive odds] The shorter-priced horses, which he laid at dynamite odds.
1926		J. Black You Can’t Win (2000) 163: I’m dynamite with them old brums in the cribs.
1930		J. Lait Gangster Girl 62: Big Boy, I’m dynamite.
1940		D. Maurer Big Con 20: His phenomenal success soon became known; the big store was ‘dynamite’.
1952		H. McCoy Corruption City 75: This is dynamite. This is what I’ve been waiting for.
1966		(con. 1958) R. Farina Been Down So Long (1972) 95: ‘Good shit, ain’t it?’ asked the vampire. ‘Dynamite, baby.’.
1975		E. Torres Carlito’s Way 9: All the losers went for the spike, and the dynamite high behind it.
1986		C. Hiaasen Tourist Season (1987) 211: Her eyes were just dynamite.
1994		N. McCall Makes Me Wanna Holler (1995) 124: He had [...] a dynamite stereo system.
2000		Guardian Rev. 12 May 7: He was almost a star in 1948. In 1950 he was box-office dynamite.
2001		Guardian Rev. 10 Mar. 2: This stuff is dynamite, Bill – what is it?
2015		S. King Finders Keepers (2016) 159: She’s one dynamite redhead and plenty smart.

3. very important, extremely effective; used both positively and negatively.

1933		Ersine Und. and Prison Sl.
1934		V.G. Burns Female Convict (1960) 78: Be careful of O’Gorman – she’s dynamite!
1945		P. Cheyney I’ll Say She Does! (1955) 128: I call it goddam urgent. It’s dynamite.
1952		W.R. Burnett Little Men, Big World 228: This statement will be dynamite, Markland. You take it yourself. No stenographer.
1963		(con. 1944) L. Glassop Rats in New Guinea 18: He’s dynamite with a Bren gun.
1975		‘P.B. Yuill’ Hazell and the Three-card Trick (1977) 182: ‘So where did all the bread for this place come from?’ she asked. ‘Ah ha [...] that’s dynamite that is.’.
1997		R. Barnard No Place of Safety 132: Because Ben and women, together, they’re dynamite.
2006		G. Iles Turning Angel 359: This is dynamite is what it is.