1.Definition: easy and not involved or complicated

"An elementary problem in statistics", "Elementary, my dear Watson"

Related Adjective(s):simple, uncomplicated, unproblematic

2.Definition: of or being the essential or basic part

"An elementary need for love and nurturing"

Related Adjective(s):basal, elemental, primary

3.Definition: of or pertaining to or characteristic of elementary school or elementary education

"The elementary grades", "Elementary teachers"