zwie·back (swēbăk′, -bäk′, swī-, zwē-, zwī-)
A usually sweetened bread first baked as a loaf and later cut into slices and toasted.
[German : zwie-, twice (from Middle High German zwi-, from Old High German; see dwo- in the Appendix of Indo-European roots) + backen, to bake (from Middle High German, from Old High German bahhan, backan).]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.