شب بخیر

What it means

شب بخیر (shab be kheyr) means “good night.” Said when leaving someone in the evening or before going to bed. The phrase is universal across registers: kids say it to parents, strangers say it on a phone call ending at 10pm.

How to use it

• شب بخیر مامان (shab be kheyr mâmân) “good night, Mom”
• شب بخیر، خوب بخوابی (shab be kheyr, khub bekhâbi) “good night, sleep well”
• شبت بخیر (shab-et be kheyr) “good night [to you]” (with possessive ending)

Compound structure

The phrase breaks into three pieces: شب (shab) “night” + به (be) “to/in” + خیر (kheyr) “goodness, well-being.” Literal sense: “the night [be] in goodness.” خیر is Arabic-origin (root kh-y-r, “good”), شب and به are pure Persian. Not a verb, but a fixed greeting formula. The parallel formula is سلام (salâm) for hello and خداحافظ (khodâhâfez) for goodbye.

Cultural note

In a Tehrani household, شب بخیر is the last verbal exchange of the day, often paired with خوب بخوابی (khub bekhâbi) “sleep well.” On phone calls it signals the call is wrapping. Younger speakers shorten it to شبت بخیر in texts and voice notes, adding the possessive -et to make it warmer.

References

• Dehkhoda
• Vajehyab