from the GNU version of the Collaborative International Dictionary of English
- n. a coupling mechanism for attaching matching cylindrical parts to each other, where each of which has an arced L-shaped slot with the longer side perpendicular to the axis of the cylinder, such that the slots slide inside each other. There is also usually a knoblike projection on the mount so that when the two parts to be connected are fully inserted in proper alignment, they are locked in place. It is designed for rapid coupling and decoupling, requiring the turning of one part through only a small arc, in place of a screw-type arrangement, which requires several full turns.
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