This masculine noun denotes the quality of being stubborn or obstinate, appearing only in Deuteronomy 9:27. Moses intercedes for Israel by asking God not to look upon 'their stubbornness, their wickedness, and their sin.' The word captures the deliberate, willful resistance to divine guidance that characterized Israel's wilderness generation. It's a quality of the heart and will rather than mere ignorance or weakness—a persistent refusal to yield to God's direction despite clear evidence and commands.