plural of mob rule

plural of work-to-rule

An instrument consisting of a rule or frame, and a plumb line, by which the batter or slope of a wall is regulated in building.

plural of batter rule

An unspoken rule.

plural of unspoken rule

A rule that is understood to apply but does not exist in written form.

plural of unwritten rule

Archaic form of rule the roost.

(engineering) A knuckle joint having shoulders that abut when the connected pieces come into line with each other, and thus permit folding in one direction only.