Origin: 1325–75; Middle English perseveren < Middle French perseverer < Latin persevērāre to persist, derivative of persevērus very strict. See per-, severe
mid-14c., from O.Fr. perseverer, from L. perseverare "continue steadfastly, persist," from persevereus "very strict, earnest," from per- "very" + severus "strict" (see severity).