From door + knob.
doorknob (plural doorknobs)
- A circular device attached to a door, the rotation of which permits the unlatching of the door.
2012 March 1, Henry Petroski, “Opening Doors”, in American Scientist, volume 100, number 2, page 112-3:
- A doorknob of whatever roundish shape is effectively a continuum of levers, with the axis of the latching mechanism—known as the spindle—being the fulcrum about which the turning takes place.
circular device attached to a door, the rotation of which permits the unlatching of a door