Cylinder
A cylinder is a three-dimensional geometric shape roughly described as a closed ended tin can; circles on both end of a rectangle rolled end-to-end.

Cylindrical objects 

In an alternate 1968,  John Christopher visually identified an UFO (specifically the ) as having "two cylindrical projections on top, one below [...] purpose undetermined," when identifying its nacelles and secondary hull." ()  also described the nacelles as "the two large glowing cylinders [...] on the outside of the ship." ()

The Nomad probe encountered by the Enterprise in 2268 was described by Spock as being "roughly cylindrical" in shape, and "a fraction over one meter" in length. ()

The Angosian escape pod detected by the  in 2366 was described as being "a cylindrical object approximately seven meters in length and three meters in diameter." ()

While instructing Julian Bashir to repair a subspace transmitter in 2370, he described one of the internal components as a "green cylinder." ()

In describing the 1936 Ford truck discovered by  in 2371, Tom Paris explained to Harry Kim that it was driven by an "internal combustion engine, a reciprocating piston cylinder design." ()

Odo also kept an infant Changeling in a glass cylinder in 2373, as he attempted to nurse it back to health. ()

The series 5 long-range tactical armor unit discovered by  in 2375 was described by The Doctor as being "over a meter in length, cylindrical, [and] quite sleek." ()

See also 
 Containment cylinder
 Shock attenuation cylinder
 Test cylinder

External link 
 

Mathematics