To send a Direct Message on twitter

sending two texts in a row without a reply inbetween.

Commonly used on twitter. It means to direct message.

To "DM" somebody u direct message them .

DM - Dungeon Master. The person who makes up the story and stuff in a game of Dungeons and Dragons.

Designated Marksman. military marksman role in a U.S. infantry squad. The DM's role is to supply rapid accurate fire on enemy targets at ranges up to 870 yds with a highly-accurate semi-automatic rifle equipped with a telescopic sight. Like snipers, DMs are trained in quick and precise shooting, but unlike the more specialised "true" sniper, they are also intended to lay down accurate rapid fire.