Elementary
来自Big Physics
late Middle English (in the sense ‘composed of the four elements, earth, air, fire, and water’): from Latin elementarius, from elementum ‘principle, rudiment’ (see element). Current senses date from the mid 16th century.
wiktionary
From Latin elementārius(“elementary”), from elementum(“one of the four elements of antiquity; fundamentals”) + -ārius(adjective-forming suffix). Cognate with French élémentaire.
etymonline
elementary (adj.)
late 14c., "having the nature of one of the four elements," from Latin elementarius "belonging to the elements or rudiments," from elementum (see element). Meaning "rudimentary, involving first principles" is from 1540s; meaning "simple" is from 1620s. In elementary school (1841) it has the "rudimentary" sense.
