To drag something is to pull it with difficulty and effort and, figuratively, to drag someone means 'to take them somewhere they don't want to go.' In computers, drag means 'to move an image by first clicking on it with the mouse.' Drag also means 'to last for too long and be boring' (in this sense it is sometimes used with on). In informal conversation a drag is something or someone boring. It is also a single puff on a cigarette.
His backpack was too heavy to wear so he dragged it around the airport.
My mom dragged me to her new boyfriend's house, despite my complaints.
Drag the picture into the chat window to send it.
The meeting dragged on and it felt like it was never going to end.
This class is such a drag and I can never wait to leave.
Tom took a long drag on his cigarette and went back to the office.
Words often used with drag
drag and drop (computer): to move an image or text holding it with the mouse, then to let it go in a particular place. "To move a file on your computer, drag and drop it into a different folder."
drag your feet (figurative): to delay or not be willing to do something. "You know you have to tell the boss what you did sometime, so stop dragging your feet and get on with it!"
in drag: wearing clothes normally worn by the opposite sex, usually when a man is wearing women's clothes. "John went to the party in drag and everyone thought he looked fabulous."
drag queen: a man who dresses like a woman, usually for a performance.
drag show: entertainment given by a man or men in drag.
Drag dates back to the second half of the 14th century and probably comes from the Middle Low German words dragge, meaning 'grapnel,' and draggen, meaning 'to dredge.' The sense of someone or something boring did not appear until the early 1920s.