Word Study
zwieback
CIDE DICTIONARY
zwieback, n. [G., fr. zwie- two, twice (see Twice) + backen to bake.].
A kind of biscuit or rusk first baked in a loaf and afterwards cut and toasted. [Webster 1913 Suppl.]
OXFORD DICTIONARY
zwieback, n. a kind of biscuit rusk or sweet cake toasted in slices.
Etymology
G, = twice baked
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