O.E.
malt (Anglian),
mealt (W.Saxon), from P.Gmc.
*maltaz (cf. O.N.
malt, Ger.
Malz "malt"), from same Gmc. root as O.E.
meltan (see
melt), probably via notion of "softening" the grain by steeping it in water before brewing, from PIE
*meld- (cf. Skt.
mrduh "soft, mild," Gk.
meldein "to melt, make liquid," L.
mollis "soft"), from base
*mel- "to grind" (cf. Gk.
myle "mill," L.
molere "to grind;" see
mallet). Finnish
mallas, O.C.S.
mlato are considered to be borrowed from Germanic.
Malt liquor (which is fermented, not brewed) first attested 1693.
Malted "a drink with malted milk" is from 1945.