Intentionally and deliberately; done with a specific goal or plan in mind.
From Old French 'purpos' (intention/proposal) via Latin 'proponere' (to put forward). The adverbial form adds '-ly' to indicate an action done with clear purpose or intention.
English has multiple adverbs for intention—'purposely,' 'deliberately,' 'intentionally,' 'on purpose'—and speakers often confuse 'purposely' with 'purportedly,' a mistake that reveals how English's abundance of similar words can trip up even native speakers.
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