I dont know if its too late, but i thought it would help someone else.
I wanted the same badly...found it eventually.
Maybe its not perfect,but to me its adequate(for my little dictionary app).
http://www.androidtech.com/downloads/wordnet20-from-prolog-all-3.zip
Its not a dump file, but a MYSQL .sql script file
The words are in WN_SYNSET table and the glossary/meaning in the WN_GLOSS table