An Etymological Dictionary of the German Language/Annotated/lauter

by Friedrich Kluge

lauter, adjective, ‘pure, mere,’ from Middle High German lûter, adjective, ‘bright, pure, clear’ Old High German lûttar, hlûttar. Since Gothic and Low German tr is not permutated in High German (compare zittern, Winter, Eiter, Otter, and bitter), Gothic hlûtrs, ‘pure,’ Anglo-Saxon hlûttor, ‘pure, clear’ (wanting in English), and Dutch louter are corresponding forms. A primary Teutonic adjective perhaps originally signifying ‘washed’ (like Latin lautus, literally ‘washed,’ then ‘splendid, magnificent’). This primary meaning may be assumed since the Teutonic root hlût, preserved only in the adjective lauter, is cognate with Greek κλυδ and κλύζω, ‘to rinse out, wash, cleanse,’ and κλύδων, ‘beating of the waves.’