D defs.my
Entry 1 sense Webster, 1913

Rock shaft

/räk shăft/ · Rock· shaft · IPA
01 A shaft that oscillates on its journals, instead of revolving, -- usually carrying levers by means of which it receives and communicates re…
  1. 1.
    A shaft that oscillates on its journals, instead of revolving, -- usually carrying levers by means of which it receives and communicates reciprocating motion, as in the valve gear of some steam engines; -- called also rocker, rocking shaft, and way shaft.(Mach.) Also: rocker, rocking shaft, way shaft