What word or phrase does your mother always say?
1560s, from Middle French cylindre (14c.), from Latin cylindrus "roller, cylinder," from Greek kylindros "a cylinder, roller, roll," from kylindein "to roll," of unknown origin.
cylinder cyl·in·der (sĭl'ən-dər)
The surface generated by a straight line intersecting and moving along a closed plane curve, the directrix, while remaining parallel to a fixed straight line that is not on or parallel to the plane of the directrix.
A solid bounded by two parallel planes and such a surface, especially such a surface having a circle as its directrix.
A cylindrical or rodlike renal cast.
A cylindrical lens.
A cylindrical metal container for gases stored under high pressure.
The set of tracks on a multi-headed disk that may be accessed without head movement. That is, the collection of disk tracks which are the same distance from the spindle about which the disks rotate. Each such group forms the shape of a cylinder. Placing data that are likely to be accessed together in cylinders reduces the access significantly as head movement (seeking) is slow compared to disk rotation and switching between heads.