Definition of behind

• the fleshy part of the human body that you sit on; "he deserves a good kick in the butt"; "are you going to sit on your fanny and do nothing?"
• in or to or toward the rear; "he followed behind"; "seen from behind, the house is more imposing than it is from the front"; "the final runners were far behind"
• remaining in a place or condition that has been left or departed from; "when he died he left much unfinished work behind"; "left a large family behind"; "the children left their books behind"; "he took off with a squeal of tires and left the other cars far behind"