simple - noun

any herbaceous plant having medicinal properties

a person lacking intelligence or common sense

simple - adjective

• having few parts; not complex or complicated or involved
• (botany) of leaf shapes; of leaves having no divisions or subdivisions
• easy and not involved or complicated
• apart from anything else; without additions or modifications
• exhibiting childlike simplicity and credulity
• lacking mental capacity and subtlety
• unornamented

simple - thesaurus

bare   childlike   elementary   mere   simpleton   uncomplicated   unproblematic   unsubdivided