simple

Where does the word "simple" come from? It comes from Latin simplex, passing through Old French before entering English (1200s).

Simple’s story begins in Latin: simplex meant “single, plain.” 'sem-', one, plus 'plicare', to fold: folded once. By medieval, the word had taken hold in Old French as simple. Also meant humble or foolish. It reached English by 1200s as simple. 'simpleton' dates from the 1600s. Today, simple means easily understood; plain.

1. Stage 1 · Latin · ancient simplex "single, plain", 'sem-', one, plus 'plicare', to fold: folded once.
2. Stage 2 · Old French · medieval simple "innocent, plain", also meant humble or foolish.
3. Stage 3 · English · 1200s simple "plain", 'simpleton' dates from the 1600s.