Collins COBUILD Advanced Learner's English Dictionary - past participle

(past participles) In grammar, the past participle of a verb is a form that is usually the same as the past form and so ends in ‘-ed’. A number of verbs have irregular past participles, for example ‘break’ - past participle ‘broken’, and ‘come’ - past participle ‘come’. Past participles are used to form perfect tenses and the passive voice, and many of them can be used like an adjective in front of a noun. N-COUNT