Why this word is great
OBDURATION — [Noun] A hardening of the heart; defiance or impenitence. From Latin obduratio ("a hardening"), from obdurare ("to harden"), from ob- ("against") + durare ("to harden"). Unlike "obduracy" (which suggests stubborn resistance to change) or "impenitence" (which centers on lack of remorse), obduration is the slow, irreversible calcification of feeling—not merely refusing to yield, but becoming incapable of yielding. It is the clenched jaw of a child refusing to cry, the cold silence of a lover who has stopped listening, or the way a once-tender conscience turns to stone under unrelenting drought. The tragedy is not in the hardness itself, but in forgetting what it ever meant to be soft.