9 letters · 20 points in Scrabble
adjective (chemistry, physics) incapable of mixing
originEtymology tree Proto-Indo-European *né Proto-Indo-European *n̥- Proto-Germanic *un- Proto-West Germanic *un- Old English un- Middle English un- English un- English mixable English unmixable From un- + mixable.
Etymology from Wiktionary, CC BY-SA 3.0