What does it mean when people say tisk tisc tisc?

Another way of saying ” Shame On You ” or you shouldn’t do/have done that.

Yes “tisk tisk” is generally a persons disaproval of anothers actions which generally indicates a silly action. Usally something a parent does to their children or grandchildren. (grit your teeth then put your tongue behind your teeth and suck air a few times and remove your tongue (fast). “This is where the gesture tisk tisk comes from”. Its usually accompanied with a stern look / shaking of the head (no gesture) and or rolling of the eyes and looking away)

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