ねばなるまい LinksSentence search for ねばなるまいSentence search for なければなるまいEdit in JMdict Expressions (phrases, clauses, etc.)1. ought to (verb); should (verb)See also ねばならない, after neg. verb stemそのことですぐになに何かてをう手を打たねばなるまい。Something must be done about it in no time.Other formsなければなるまい Discussions Log in to talk about this word.