German

Noun

Zwieback m ‎(genitive Zwiebacks or Zwiebackes, plural Zwiebacke or Zwiebäcke)

1. zwieback (toasted sweetened bread)

English

Zwieback

Noun

zwieback ‎(plural zwiebacks)

1. a usually sweetened bread enriched with eggs that is baked and then sliced and toasted until dry and crisp
2. a teething food for toddler children

References

1. ↑ “zwieback” in Douglas Harper, Online Etymology Dictionary (2001).; though it gives Zweiback as the source.