▪ I. chad
I had: see ch pron.
▪ II. chad, n.2 Telegr. and Computing.
(tʃæd)
[Origin unknown.]
(A piece of) the waste material removed from punched cards or tape during punching.
| 1959 J. W. Freebody Telegr. xi. 460/2 The small hinged discs of paper, called ‘chads’, remain attached to the body of the tape. 1968 J. Blackburn Nothing but Night vii. 64 The machines..spewed out the sixty-four-row punch cards... At the base of each machine was a vacuum tube to remove the dust and the chads. 1982 Computerworld 9 Aug. 59 The reader head is mounted on the front of the unit next to the chad box. |
Hence ˈchadless a., not producing or accompanied by chads.
| 1959 J. W. Freebody Telegr. xi. 460/2 In order..that the printed characters are completely legible, the tape is perforated by the chadless method. 1971 Gloss. Electrotechnical, Power Terms (B.S.I.) iii. iii. 19 Chadless perforation. 1984 U.S. Patent 4,425,394 1 Each tag has a chadless hole provided by a pattern of knife cuts. |
▪ III. chad
var. of shad, a fish.