Meaning: ないだろう; negative auxiliary word used to express conclusion in the future tenseart. a, indefinite article used with nouns; an, indefinite article used before a word which starts with a voweladj. (Kanji=或,或る) some, being an unknown or unspecified amount, undetermined, approximatev. (Kanji=有る) be, exist; abound; fare; have, keep; ownv. (Hira=ある) be, exist; abound; fare; have, keep; own