8 letters · 15 points in Scrabble
originFrom Middle English hondfast, past participle of Middle English hondfesten (“to betroth”), from Old Norse handfesta (“to strike a bargain, pledge”), itself from hönd (“hand”) + festa (“to fasten, fix, affirm”), perhaps from a Proto-Indo-European root *pHst-.
Etymology from Wiktionary, CC BY-SA 3.0