Noun:
1: simple any herbaceous plant having medicinal properties
2: simple, simpleton a person lacking intelligence or common sense
Adjective:
1: uncomplicated, unsophisticated, simple, unanalyzable, undecomposable, simplex having few parts; not complex or complicated or involved; "a simple problem"; "simple mechanisms"; "a simple design"; "a simple substance"
2: elementary, easy, unproblematic, uncomplicated, simple easy and not involved or complicated; "an elementary problem in statistics"; "elementary, my dear Watson"; "a simple game"; "found an uncomplicated solution to the problem"
3: simple, plain, bare, mere apart from anything else; without additions or modifications; "only the bare facts"; "shocked by the mere idea"; "the simple passage of time was enough"; "the simple truth"
4: dewy-eyed, round-eyed, simple, wide-eyed, childlike, naive, naif exhibiting childlike simplicity and credulity; "childlike trust"; "dewy-eyed innocence"; "listened in round-eyed wonder"
5: dim-witted, retarded, simple-minded, simple, half-witted lacking mental capacity and devoid of subtlety
6: pandurate, two-needled, obtuse, five-needled, simple, oblanceolate, needled, elongate, sagittiform, lancelike, reniform, acuminate, panduriform, unlobed, three-needled, deltoid, acicular, swordlike, sagittate, orbicular, obovate, dolabriform, four-needled, sword-shaped, acerate, caudate, acerose, needle-shaped, arrow-shaped, oblong, kidney-shaped, fiddle-shaped, shield-shaped, linear, orbiculate, bladelike, elliptic, cordiform, spatulate, spearhead-shaped, wedge-shaped, hastate, dolabrate, ovate, lanceolate, perfoliate, heart-shaped, spatula-shaped, cuneate, ensiform, lyrate, peltate, unsubdivided, apiculate, cordate (botany) of leaf shapes; of leaves having no divisions or subdivisions
7: plain, simple unornamented; "a simple country schoolhouse"; "her black dress--simple to austerity"