What is holding stoutly to one's opinion or purpose; obstinate; stubborn. -- Te*na"cious*ly, adv. -- Te*na"cious*ness, n called?

tenacious — Holding stoutly to one's opinion or purpose; obstinate; stubborn. -- Te*na"cious*ly, adv. -- Te*na"cious*ness, n. (Webster's 1913.)

Sources