8 letters · 12 points in Scrabble
adjective tenaciously unwilling or marked by tenacious unwillingness to yield
adjective not responding to treatment
originFrom Middle English stiborne, stibourne, stoburn, stoburne, styburne, stiborn, of uncertain origin; one hypothesis is that it may be from Old English *stybbor, from Old English stybb (“a stump, stub”) + -or (adjective-formation suffix, as in bitor, whence English bitter).
Etymology from Wiktionary, CC BY-SA 3.0