plastic pig 

A PCSO (Police Community Support Officer). They have no power of arrest so they are often called plastic police, add that to pigs for police you get plastic pigs. It's very derogatory as it implies they are useless.

You can't arrest me you plastic pig!

plastic pig by sci_fi_rocks August 15, 2016

plastic pig 

Term for a Reliant Robin, small 3 wheeled car/van made from GRP in Tamworth. Made famous as the transport for del boy in the TV show only fools and horses. Very slow and has a tendency to roll over when cornering. Used as a term of abuse for any slow or crap car. See also metrocab.

Bloke: "Why were you so late?"
Another bloke: "Coz i was stuck behind a plastic pig all the way up the M42

plastic pig by oracle August 19, 2004

plastic pig 

Its a nickname for a 3 wheeled British car called a Reliant Robin. With a body made out of fibre-glass and a very small engine. Known to tip round corners and were given to the disabled and old as 'invalid Carriges', usually in a pale blue colour. Can be driven on a motorbike license.

'I once saw a plastic pig go to fast round a corner and tip onto its side!'

plastic pig by Evil-Ernie June 6, 2003