ぬ

ぬ is an old negative ending with the same meaning as ない, and it goes on the same stem: しらない知らない becomes しら知らぬ. It sounds literary or old-fashioned, and today you meet it mostly in set phrases, proverbs and writing.

する takes the old stem せ, not し: せぬ, never ×しぬ. くる来る becomes こ来ぬ, read こぬ.

Before a noun and at the end of a sentence

ぬ does the two jobs ない does: it describes a noun, and it ends a sentence. To link it to the next clause, though, you need ず or ずに, which are forms of the same old negative.

• × 何も言わぬ帰った → 何も言わずに帰った

ぬ or ない

The meaning is the same; the register is not. In conversation the negative is ない, and ぬ in an ordinary sentence sounds stiff or theatrical, like a character in a period drama.

The set phrases are the exception. しら知らぬま間に, みて見てみぬ見ぬふり, おもわ思わぬ and やむをえ得ぬ are ordinary modern Japanese, and you learn them as vocabulary.

Usage notes

These go beyond ぬ as a plain negative.

ねばならぬ, "must"

ねば is the "if not" form of ぬ. ねばならぬ and ねばならない mean "must", a written version of なければならない.

ん in speech

The spoken form of ぬ is ん: わからん, しら知らん. In western Japan it is the everyday plain negative; elsewhere it sounds blunt and casual. The ん in ません is the same ending.