Chad (paper) device which will not punch a complete circle in the tape but, instead, will only cut approximately three-quarters of the circumference of a circle ... thereby leaving a movable, or hinged, lid of paper in the tape." In the "New Hacker's Dictionary", two unattributed and likely humorous derivations for "chad" are offered, a back-formation from a personal name "Chadless" and an acronym for "Card Hole Aggregate Debris". Other etymologies claim derivation from the Scottish name for river gravel, "chad", or the British slang for louse, "chat". When a chad is not fully detached, it is described by various terms corresponding
Hole punch Hole punches for industrial volumes (hundreds of sheets) feature very long lever arms, but function identically. Another mechanism uses hollowed drills which are lowered by a screwing action into the paper. The paper is cut and forced up into the shaft of the drill to be later discarded as tightly packed columns of waste paper. This method allows a small machine to cut industrial volumes of paper with little effort. The most common standard dimension and location of filing holes punched in paper is International Standard ISO 838. Two holes with a diameter of 6±0.5 mm are punched into the