look up any word, like muddin:
 
1.
Secretly; covertly.
He was running a numbers bank on the QT while he led the campaign against casino gambling.
by octopod November 23, 2003
 
2.
Secret, usually in the sense of "under your hat"
"I'll tell you if you promise to keep it on the QT. No one can know"
by Dana Mix August 17, 2003
 
3.
On the down low.
I listen to Justin Timberlake on the QT.
by T November 22, 2003
 
4.
secretely planning to fulfil one's vested interests, usually at the cost of others.
The demagogue is always on the qt as to how to come to power.
by uttam maharjan April 12, 2011