11 letters · 27 points in Scrabble
originFrom Middle English thankworthy, thank-worthy, þankeworþi, probably an alteration (with -y) of earlier Middle English thanke worth, thankworth, þancwurðe (“thankworthy”), from Old English þancwyrþe, þancweorþ (“thankworthy, deserving thanks, acceptable”), equivalent to thank + -worthy. Cognate with German dankwürdig (“worthy of thanks”).
Etymology from Wiktionary, CC BY-SA 3.0