Sliding into DMs refers to the online practice of contacting someone in a direct message in a smooth, slick and impressing way.
It is usually made with the intent of awakening a romantic interest in the person one is contacting.
The expression emerged on Twitter where the feature of private messaging is called direct message, abbreviated as DM.
“Sliding into DMs” first appeared on the social media site in 2010 and would start to gain popularity in 2013.
“Sliding into DMs” would first appear in numerous tweets in 2013, being first defined on Urban Dictionary in 2014.
Following 2014, the expression would be adopted by users on all sorts of social media sites, including Facebook, Instagram as well as dating sites like OkCupid.