Definition of malts:
(n) :
Malted grain (sprouted grain) (usually barley), used in brewing and otherwise.
(n) :
Malt liquor, especially malt whisky.
(n) :
(US, informal) A milkshake with malted milk powder added for flavor.
(v) :
(transitive) To convert a cereal grain into malt by causing it to sprout (by soaking in water) and then halting germination (by drying with hot air) in order to develop enzymes that can break down starches and proteins in the grain.
(v) :
(intransitive) To become malt.
(n) :
Maltose-rich sugar derived from malted grain.