on the down-low

• on the down low, on the DL, on the low, on the downlow

• Audio (General Australian):

  (file)

on the down-low

2. (US, idiomatic, slang, euphemistic) In secret or nearly so, on a need-to-know basis.

   I'll tell you, but keep it on the down-low.

4. (US, idiomatic, slang, euphemistic) Secretly sleeping with someone other than one's partner.
   • 1995 December 11, “Down Low (Nobody Has to Know)”‎^[1]performed by R. Kelly:

     And keep it on the down low
     Nobody has to know

6. (African-American Vernacular, LGBTQ) Of a man, publicly identifying as heterosexual but secretly having sex with men.

• See also Thesaurus:covert

• “down-low”, in Cambridge English Dictionary, Cambridge, Cambridgeshire: Cambridge University Press, 1999–present.
• “on the downlow”, in Collins English Dictionary.