to mean a device adapted to interact in a mechanical assembly of interacting parts that serves to transmit motion or to change the rate or direction of motion funk and wagnalle u201c standard college dictionary u201d harcourt brace amp world cw1968 in another regard the terms u201c helical gear u201d are herein intended to mean a gear having teeth arranged in the configuration of a helix u201c machinery 39 s handbook u201d 25 ed industrial press inc new york 1996 in another regard the term u201c motor u201d is herein intended to mean something that imparts or produces motion funk and wagnalle u201c standard college dictionary u201d harcourt brace amp world cw1968 in still a further regard the terms u201c pin coupling u201d are herein intended to mean a form of slip joint coupling to a shaft of a motor in yet another regard the terms u201c pinion gear u201d are herein intended to mean a toothed wheel driving or driven by a larger cogwheel funk and wagnalle u201c standard college dictionary u201d harcourt brace amp world cw1968 in yet still an additional regard the terms u201c rolling traction u201d or u201c rotary traction u201d are herein intended to mean the act of drawing as by motive power over a surface using rolling or rotational movement respectively such as a wheel or tire the term u201c toroid u201d is herein intended to mean a surface generated by the rotation of any closed plane curve about and axis lying in its plane but external to it e g donut shaped funk and wagnalle u201c standard college dictionary u201d harcourt brace amp world cw1968 one highly beneficial.