DM
An abbreviation for "direct message," a form of private communication on social media sites or Internet forums. It is most commonly used as a verb. I'll DM you the address. DM me if you have any questions. Send me a DM so it's not public.
DM me
A request to send one a direct message, a form of private communication on social media sites or Internet forums. DM me if you have any questions.
slide into (one's)/the DMs
slang To successfully flirt with someone via direct message (DM) on social media. If you're trying to slide into your crush's DMs, don't use a cheesy pick-up line. A: "I just slid into the DMs and asked her out on a date." B: "Wow, I can't believe that actually worked!"