でなければならない

also: でなければいけない · でなければならぬ

Common word

Meanings

expression

must be; have to be; ought to be

Used after a noun or na-adjective stem with で to state a required identity, status, quality, or condition. It is the copular counterpart of なければならない: literally, 'if it is not ..., it will not do.'

See also: である · なければならない

リーダーは常つねに冷れい静せいでなければならない。
A leader must always be calm.
申しん請せい者しゃは十じゅう八はっ歳さい以い上じょうでなければいけない。
Applicants must be at least eighteen years old.
指し導どう者しゃは公こう正せいでなければならぬ。
A leader must be fair.

Written forms

でなければいけない
Everyday variant with いけない; often feels a little more conversational than でなければならない.
でなければならぬ
Stiff, literary, or old-fashioned variant using ならぬ instead of ならない.

Similar words

なければならない
General 'must; have to' pattern used after predicates such as verbs and adjectives; でなければならない is the copular 'must be ...' form used especially after nouns and na-adjectives.
である
Formal copula meaning 'to be'; でなければならない is related to its negative conditional form, expressing that not being so is unacceptable.
べき
Also means 'should' or 'ought to,' but often expresses judgment, duty, or advisability; でなければならない states a required state or condition more directly.

Meanings

Etymology