Definition of minor diameter in English English dictionary
The innermost diameter of a cylindrical, circular, or helical feature, such as a screw thread, gear teeth, etc
This is the diameter of an imaginary cylinder which just touches the roots of an external thread, or the crests of an internal thread
The smallest diameter of the thread of a screw or nut The term "minor diameter" replaces the term "core diameter" as applied to the thread of a screw and also the term "inside diameter" as applied to the thread of a nut