Meaning of ELEMENTARY in English
adj pertaining to one of the four elements, air, water, earth, fire.
2. elementary ·adj having only one principle or constituent part; consisting of a single element; simple; uncompounded; as, an elementary substance.
3. elementary ·adj pertaining to, or treating of, the elements, rudiments, or first principles of anything; initial; rudimental; introductory; as, an elementary treatise.
Webster English vocab. Английский словарь Webster. 2012