VERB: to do something stupidly or clumsily; mostly used by those attending King's College, Auckland, and their associates.
Derived from L Plate the plates that Learner drivers must display when driving.
Commonly used in conjunction with retard wanker eatass and other insults. Generally only used by teenage males.
Guy 1: Hey, Tom, where's mum's car? I want to go out.
Brother: Sorry, I crashed it coming into K-Rd. The cops dropped me off. Gutted eh?
Guy 1: Well, you fully L-Plated that, retard.
Guy 1: Man, I am so screwed..!
Friend: What's up?
Guy 1: I fully L-Plated it with Christie - called her Jess. Fuck.