simpleness (Noun) — A lack of penetration or subtlety. ex. "they took advantage of her simpleness"
simpleness (Noun) — The quality of being simple or uncompounded. ex. "the simpleness of a crystal"
simpleness (Noun) — Freedom from difficulty, hardship or effort.
simpleness (Noun) — Lack of ornamentation.
simpleness (Noun) — Absence of affectation or pretence.