The letters used for German are the ASCII letters. German umlauts and
eszett are replaced by their two-letter substitutions (ae, oe, ue, ss).
Diacritics in German words derived from foreign languages are dropped
(e.g. Cafe, Chateau, Senorita).

All words are legal apart from proper nouns and abbreviations. If in
doubt, a word is legal only if it is listed (in its base form) in the
Duden dictionary (http://www.duden.de), which is the most widely used
source for the spelling of German, and the Duden says that the word type
is not a proper noun or an abbreviation. This rule is also applied to
compound words: a compound word needs to be listed in the Duden to be
legal (otherwise it is too easy in German to create an infinite number
of new words by simple composition).

The original word list for German was created using igerman98-20110609
(http://www.j3e.de/ispell/igerman98/index_en.html). Inflections were
generated using hunspell (http://hunspell.sourceforge.net/). Some
dictionaries of igerman98 that contained only proper nouns and
abbreviations were not used at all and the list was heavily edited
manually afterwards to remove remaining proper nouns, illegal compound
words and other errors.

The list probably still contains words that are not legal by the above
rules and is still incomplete. Please help to improve it and report any
illegal or missing words you find.
