Толковый словарь английского языка Oxford English Reference - opportune

adj. 1 (of a time) well-chosen or especially favourable or appropriate (an opportune moment). 2 (of an action or event) well-timed; done or occurring at a favourable or useful time. Derivatives opportunely adv. opportuneness n. Etymology: ME f. OF opportun -une f. L opportunus (as OB-, portus harbour), orig. of the wind driving towards the harbour