ON THE Q.T., phr. (common).—On the QUIET: also ON THE STRICT Q.T.

1

  c. 1870.  Broadside Ballad, ‘The Talkative Man from Poplar.’ Whatever I tell you is ON THE Q.T.

2

  1893.  P. H. EMERSON, Signor Lippo, ix. We asked him ON THE Q.T. how it was.

3