Green’s Dictionary of Slang

1. (US) a promiscuous woman, a prostitute .

1833

Ely’s Hawk & Buzzard (NY) Sept. 14 n.p.: Poll Snooks [...] was a young lady of blooming qualifications [...] none of your fly away rat traps, but [...] swet as a cowslip .

2. a shabby or ramshackle building or dwelling.

1886		M.E. Braddon Mohawks III 154: Marjory’s! What the sponging-house in Shoe Lane! [...] ’tis an execrable den, but not a whit worse than their other holes. I have hobbed and nobbed with my friends in most of their rat-traps, and know the geography of them.
1891		H.B. Marriott-Watson Web of the Spider 320: You went a funny way about it, but let me out of this rat-trap.
1919		A. Baer Two & Three 26 Apr. [synd. col.] Hades apartments [...] Built by Rattrap construction company and designed by Jogsaw puzzle syndicate.
1919		C. Hamilton William – An Englishman (1999) 213: Then he too rose in his turn, and went back to the town – to the rat-trap wherein he made war!
1934		H. Miller Tropic of Cancer (1963) 209: I looked at a sort of rat trap [...] with balconies running around the courtyard.
1947		W. Motley Knock on Any Door 418: You drove to the rat-trap dance hall – tavern – whatever it is?
1959		L. Hansberry Raisin in the Sun I i: We’ve put enough rent into this here rat trap to pay for four houses by now.
1965		(con. 1940s) Malcolm X Autobiog. (1968) 161: The slum blocks of old rat-trap apartment houses.
1978		Boomtown Rats ‘Rat Trap’ 🎵 It’s a rat trap, Judy, and we’ve been caught.
1991		W.T. Vollmann Whores for Gloria 23: Inside all the rat-trap apartments it was too hot to sleep.
2004		J.A. Juarez Brotherhood of Corruption 137: [A] foot chase took us through a chain of these rattraps [...] Many of the apartments were tiny and squalid.
2018		I. Welsh Dead Man’s Trousers 165: [A] party in some west Edinburgh rat trap.

3. a vehicle, esp. as rolling rat trap.

1929		(con. 1917–18) C. MacArthur War Bugs 287: We threw open the doors of our rolling rat-traps and sniffed the sea.
1955		J.P. Donleavy Ginger Man (1958) 182: Perhaps you’d rather that I kick this rolling rat trap to pieces.
1959		J. Yates-Benyon Weak and the Wicked 122: She was a ’ell o’ a ship, a real rat trap.