An Etymological Dictionary of the German Language/Annotated/mehr
mehr, adjective and adverb, ‘more,’ from Middle High German mêr; comparative of viel; also, doubly compared, mêrer, mē̆rre, ‘greater or larger’ (of space, number, and value); further indeclinable mêre, mêr, mê, ‘plus’; Old High German mêr, undeclin. neuter and comparative adverb, ‘more, plus, magis, amplius,’ adjective mêro, ‘major, greater’ (also with the addition of the comparative suffix mêrôro, mêriro, ‘major’). Old High German mêro originated in maizo, Gothic maiza, the -iza- of which is the Old Teutonic comparative suffix (compare besser, Gothic batiza; höher, Gothic hauhiza); compare Anglo-Saxon mâ, adverb and neuter substantive, ‘more,’ adjective mâra, English more. The corresponding superlative is meist. Gothic maiza, for *majiza, belongs, with the Gothic superlative maists (see meist), to the Teutonic adjective mê-rs, ‘projecting,’ discussed under Märchen.