Meaning

noun someone regarded as certain to succeed

noun a notation cancelling a previous sharp or flat

noun (craps) a first roll of 7 or 11 that immediately wins the stake

originInherited from Middle English natural, borrowed from Old French natural, naturel, from Latin nātūrālis, from nātus, the perfect participle of nāscor (“be born”, verb). Displaced native Old English ġecynde. By surface analysis, natur(e) + -al.

Etymology from Wiktionary, CC BY-SA 3.0