Noah Webster
Elementarity
ELEMENTAR'ITY
ELEMENT'ARY, adjective Primary; simple; uncompounded; uncombined; having only one principle or constituent part; as an elementary substance. Elementary particles are those into which a body is resolved by decomposition.
1. Initial; rudimental; containing, teaching or discussing first principles, rules or rudiments; as an elementary treatise or disquisition.
2. Treating of elements; collecting, digesting or explaining principles; as an elementary writer.