Also spelled on the q.t., or on the QT.
Meaning of Idiom ‘On the Q.T.’
‘On the Q.T. means quietly, discreetly or without anyone knowing. This slang idiom usually refers to an action being undertaken.
Examples Of Use
“I’m planning a surprise party for Mary. Keep it on the q.t.”
“They replaced the lead actor on the q.t.”
Origin
Q.T. is a humorous abbreviation for quiet. So, as an idiom, on the q.t. is the same thing as ‘on the quiet’ and is simply a way of saying quietly. It has been used in English since at least 1870.
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