9 letters · 10 points in Scrabble
adjective not given medical care or treatment
adjective not subjected to chemical or physical treatment
adjective (of a specimen for study under a microscope) not treated with a reagent or dye
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 treated English untreated From un- + treated.
Etymology from Wiktionary, CC BY-SA 3.0