A serious attempt or effort to achieve something, especially something difficult or challenging. The British spelling of 'endeavor,' often used to suggest noble or ambitious undertakings.
From Middle English 'endeveren,' meaning 'to exert oneself.' Literally 'put oneself in duty,' from 'en-' (in) plus 'devoir' (duty, from French). The spelling with 'ou' reflects British orthographic conventions.
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