In a way that occurs at the same time or by chance; simultaneously or as a coincidence.
From 'coincident' (adjective) + '-ly' (adverb-forming suffix). The adverbial form modifies verbs or entire clauses to indicate manner or timing.
Coincidently, the word 'coincidently' is often considered non-standard by grammarians who prefer 'coincidentally'—which is itself a linguistic coincidence worth pondering!
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