The present participle of 'diploma' when used as a verb; the act of awarding or earning a diploma.
From 'diploma' + '-ing' (present participle). This rare gerund form emphasizes the action of diploma-granting or completion of diploma requirements.
Using 'diploma' as a verb ('The school is diplomaing graduates') sounds awkward to modern ears, which is why we say 'graduating' instead—showing how some word uses fade as languages evolve.
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