Indirectly tweeting something about someone without mentioning their name. Even though their name is not mentioned, it is clear who the person tweeting is referring to.
Are you joking #sorude #subtweeting
by fridaymyday September 19, 2013
A form of tweeting used only by pussies because they are too scared to @ someone
"Hey go check twitter I think Tina is subtweeting you." "Oh man, she's such a pussy"
by Jake kanjam June 04, 2014