Hangul syllable janh

It marks a point as shared or worth confirming. In -잖아 and polite -잖아요, the speaker presents the point as something the listener already knows or can agree with. It can remind, correct, justify, or invite a “right?” response.

A 2020 study of Seoul university students reported gender-linked differences in its use: women in the sample used more agreement-seeking and politeness strategies, while men used more direct reminders. That finding describes the study's participants, not all Korean speakers.

Why does 잖 mean 'not'?

It can, but the ending usually does more than negate. A 2008 historical-corpus study traces it from the negative construction -지 아니하다, through -지 않다, to -잖-. The ending later developed conversational uses beyond literal negation.

That history connects today's reminders and agreement checks to an older negative form. In its sentence-ending use, 잖 frames a point as shared or already familiar, rather than simply saying that something is not the case.

What does 잖아 mean in a message?

Read it as a reminder, correction, or agreement check. A falling 그렇잖아 presses a point as already established; rising 그렇잖아? asks for agreement. Text loses the spoken contour, so punctuation and the surrounding message can hint at the force without settling it.

A 2016 conversation-corpus study describes uses that align with an earlier claim as well as uses that push against it: the ending presents the speaker's account as common ground. A 2021 National Institute of Korean Language dialect report records Jeolla -잔해 as a counterpart to standard -잖아.