zwieback

Etymology
From, from +  (i.e “twice-baked”), a calque of  (but not to be confused with it).

Noun

 * 1) A form of rusk, usually sweetened bread enriched with eggs that is baked and then sliced and toasted until dry and crisp; considered easy to digest and therefore given to the ill and used as a teething food for toddlers.
 * 2) * Ogden Nash, Adventures Of Isabel
 * She nibbled the zwieback that she always fed off, And when it was gone, she cut the giant's head off.

Translations

 * Finnish:
 * German:
 * Italian: fetta biscottata
 * Polish:
 * Romanian:
 * Russian: сдобный сухарь
 * Turkish:
 * Ukrainian: сухар