Verb
fall off the back of a lorry (third-person singular simple present falls off the back of a lorry, present participle falling off the back of a lorry, simple past fell off the back of a lorry, past participle fallen off the back of a lorry)
(idiomatic, Britain, euphemistic) Of an item of merchandise, to come into a person's possession without having been paid for; to have been acquired illegally.