Main Entry: ¹ought

Pronunciation: \ˈȯt\

Function: verbal auxiliary

Etymology: Middle English oughte (1st & 3d singular present indicative), from oughte, 1st & 3d singular past indicative & subjunctive of owen to own, owe — more at owe

Date: 12th century

—used to express obligation <ought to pay our debts>, advisability <ought to take care of yourself>, natural expectation <ought to be here by now>, or logical consequence <the result ought to be infinity>