Grammar. a participle form, in English having the suffix -ing, denoting repetition or duration of an activity or event: used as an adjective, as in the growing weeds, and in forming progressive verb forms, as in The weeds are growing.
British Dictionary definitions for present-participle
a participial form of verbs used adjectivally when the action it describes is contemporaneous with that of the main verb of a sentence and also used in the formation of certain compound tenses. In English this form ends in -ingCompare gerund