mid-15c., from Old Norse draga, or a dialectal variant of Old English dragan "to draw," both ultimately from Proto-Germanic *dragan "to draw, pull," from PIE root *dhragh- "to draw, drag on the ground" (cf. Sanskrit dhrajati "pulls, slides in," Russian drogi "wagon;" but not considered to be directly the source of Latin trahere).
Meaning "to take a puff" (of a cigarette, etc.) is from 1914. Related: Dragged; dragging. Drag-out "violent fight" is from c.1859. To drag (one's) feet (1946, in figurative sense) supposedly is from logging, from a lazy way to use a two-man saw.
c.1300, "dragnet," perhaps from a Scandinavian source (cf. Swedish dragg "grapnel") or from Old English dræge "dragnet," related to dragan "to draw" (see drag (v.)).
Sense of "annoying, boring person or thing" is 1813, perhaps from the notion of something that must be dragged as an impediment. Sense of "women's clothing worn by a man" is said to be 1870 theater slang, from the sensation of long skirts trailing on the floor (another guess is Yiddish trogn "to wear," from German tragen); drag queen is from 1941.
Drag racing (1947), is said to be from thieves' slang drag "automobile" (1935), perhaps ultimately from slang sense of "wagon, buggy" (1755), because a horse would drag it. By 1851 this was transferred to "street," as in the phrase main drag (which some propose as the source of the racing sense).
In addition to the time trials there are a number of "drag races" between two or more cars. They are run, not for record, but to satisfy the desire of most Americans to see who can get from here to there in the fastest time. ["Popular Mechanics," January 1947]
A force acting on a moving body, opposite in direction to the movement of the body, caused by the interaction of the body and the medium it moves through. The strength of drag usually depends on the velocity of the body. ◇ Drag caused by buildup of pressure in front of the moving body and a decrease in pressure behind the body is called pressure drag. It is an important factor in the design of aerodynamically efficient shapes for cars and airplanes. ◇ Drag caused by the viscosity of the medium as the molecules along the body's surface move through it is called skin drag or skin friction. It is an important factor in the design of efficient surface materials for cars, airplanes, boat hulls, skis, and swimsuits. Compare lift. See Note at aerodynamics.