plural of Johansson block

A precision-ground template used for the calibration of mechanical measuring devices.

gauge block

plural of gauge block

(transitive) To obstruct. / To book, set aside (an unbroken period of time to do an activity).

A power strip.

a block on which hats are formed or dressed

plural of hat block

plural of stumbling block

(music) A wooden block in the pianoforte, often made of several pieces, into which the wrest-pins are driven.