Green’s Dictionary of Slang

plastic n.

1. any form of credit card; thus (US) work plastic v., to obtain goods using a stolen credit card.

[US]D. Jenkins Dead Solid Perfect 209: I told her there was plenty of money in the checking account, and of course she had a whole purse full of plastic.
[US]N. Pileggi Wiseguy (2001) 179: He thought Stacks got whacked in some drug deal or over some plastic.
[UK]K. Lette Foetal Attraction (1994) 242: The only plastic you’ve got left is your organ donor card.
[Scot]I. Welsh Filth 256: Tidy fanny wi real brains always take the short-cut by marrying wedge and getting sorted out with some plastic.
[Aus]P. Temple Black Tide (2012) [ebook] Might not be on his plastic. Might have paid cash.
[UK]Guardian 21 Jan. 32: How is we footballers going to keep up our rep as the biggest of spenders if he can swan around unhindered melting the plastic?
[NZ]McGill Reed Dict. of N.Z. Sl. 159: plastic fantastic [...] 2. Credit cards. At Christmas a lot of us thrash the plastic.
[UK]K. Sampson Killing Pool 141: I slot the plastic, bang in the PIN.
[US]C. Hiaasen Squeeze Me 15: ‘How much is this gonna cost?’ ‘Four hundred dollars.’ [...] ‘You take plastic?’.
[Ire]P Howard Braywatch 28: ‘That’ll be €52.50’ [...] I hand the woman my plastic.

2. (UK Und.) plastic explosive, used for safe-breaking.

[Ire]J. Morrow Confessions of Proinsias O’Toole 133: Have you any plastic handy? – Enough for a small safe.
[UK](con. 1950s–60s) in G. Tremlett Little Legs 114: All you have to do is pop the plastic in a keyhole and use a detonator.
[UK]J. Osborne Déjàvu Act I: When I hear ‘money for the arts’, I reach for my Semtex plastic.

In phrases

on the plastic

(UK Und.) using stolen credit cards for a variety of frauds and swindles.

[UK]D. Powis Signs of Crime 197: Plastic, on the Defrauding persons, banks and stores with false credit or bank cards.