mid-14c., from Old French perseverer "continue, persevere, endure" and directly from Latin perseverare "continue steadfastly, persist," from persevereus "very strict, earnest," from per "very" (see per) + severus "serious, grave, strict, austere," which is probably from PIE root *segh- "to have, hold," on the notion of "steadfastness, toughness." Related: Persevered; persevering.
