drawtube

drawtube [draw-toob, -tyoob] Word Origin noun

1. a tube sliding within another tube, as the tube carrying the eyepiece in a microscope.

Origin of drawtube First recorded in 1890–95; draw + tube British Dictionary definitions for drawtube drawtube noun

1. a tube, such as one of the component tubes of a telescope, fitting coaxially within another tube through which it can slide