Comprehensive Dictionary of Food, Erich Lück:

predough -> sponge
sponge; sponge dough; predough: Vorteig, Hefestück

Preferment
Also called pre-dough, poolish, or biga (Italian breads); a mixture of flour, water and yeast that is prepared and fermented before the actual bread dough in order to help with rise, texture and flavor quality of the finished product.
http://wizzley.com/focaccia-bread-recipe/

A preferment is a catch-all word describing any amount of flour, water and biological leavening agent (as opposed to chemical) which the baker prepares before mixing the dough. In almost all cases, the preferment will not contain salt, since salt inhibits fermentation. (But there are exceptions, such as the rye salt sourdough or the pate fermente, discussed in the next post.) Fermentation is the source of the gases that make the bread rise, but more importantly, fermentation creates organic acids that strengthen the gluten and facilitate the creation of the thin sheets that trap the CO-2 from fermentation. Every artisan baker strives to create signature flavors, and preferments are the primary tool.
http://breadhealthy.com/artisan-bread/bread-baking-glossary/...


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Note added at 17 mins (2012-04-13 17:37:17 GMT)
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http://de.wikipedia.org/wiki/Vorteig
http://en.wikipedia.org/wiki/Pre-ferment