When you encounter a word that you feel doesn't belong in the dictionary, you can permanently exclude that word by pressing Ctrl-E. The word is written to WordDictionaryExclusions.utf8 (the word exclusions file) in your Chinese Toolbox document folder. As long as you keep this file, the word you exclude will continue to be excluded throughout future Chinese Toolbox releases and word dictionary file (cedict_ts.u8) updates. The word exclusions file can be edited, but it must always be saved in UTF-8 text format.
To reverse all word exclusions, quit Chinese Toolbox and delete the word exclusions file from your Chinese Toolbox document folder.
To permanently remove a word from the word dictionary, ensure that the word you want to exclude is shown in the Word Dictionary window, then press Ctrl-E.