Oyasumi (おやすみ - Good Night)

Oyasumi

The most common phrase used when you go to bed in Japan is 'oyasumi' (おやすみ).

If you want to be a little more polite, you can say 'oyasuminasai' (おやすみなさい) by adding 'nasai' (なさい).

'O' (お) is a polite prefix, 'yasumi' (やすみ) means "to rest," and 'nasai' is short for 'nasatte kudasai' (なさって下さい), which means "please do that."

That is to say, the literal meaning of 'oyasuminasai' is "Please get rest."

You can use this phrase not only when you go to bed but also when you say goodbye to someone at night.

おやすみ

日本の就寝時の挨拶でもっとも一般的なのは「おやすみ」です。

丁寧に言いたいときは「なさい」をつけて「おやすみなさい」と言います。

「お」は丁寧の接頭辞、「やすみ」は "rest," 「なさい」は "please do that" を意味する「なさって下さい」を省略した語です。

すなわち「おやすみなさい」は "Please get rest" という意味になります。

就寝時だけでなく、夜に人と別れる際にもよく使われます。

• That is to say, the literal meaning of 'oyasuminasai' is "Please get rest."
• In other words, the literal meaning of 'oyasuminasai' is "Please get some rest."

  You can also say 'In other words' instead of 'That is to say' - both are fine!
  We should use 'some' before rest in this case.

Nice entry! I enjoyed reading it and I learnt something new (^-^)
英語は上手ですね！