Tsk tsk

[Justin Bieber]

A sound made with the mouth to indicate that someone is being naughty/disobedient.

[Britney]

1/ I disapprove;
2/ Youve been naughty;
3/ What a shame;
4/ How embarrassing for you;
5/ Isnt life unfair sometimes!
6/ I commiserate with your sadness/suffering/ill treatment.
Sometimes represented as Tch Tch or Tut Tut, Tsk is more a vocal sound than an actual word, and pronounced by forming a T-sound, but then sucking lightly on the palate. People only say Tisk tisk as a parody of the actual sound, making fun of the act of disapproval or shaming.

[Tanya Shivari]

the clicking sound of the tongue pressing against the roof of the mouth

used to express regret

synonymous to what a shame