I can't even figure out how to follow jonsi's suggestion, but I don't know if I need to. (If I select Dictionary.app in Finder and then depress "shift" and hit command-O I wind up at ~/Documents. )
Please list the sources you've now got in Dictionary.app.
Thanks.
The new Great Equalizer is the SEND button.
In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire