Type a phone number into the edit box, press the return key, and a list of words/digits will appear. Minimum Word Length sets the minimum length of words considered so as to prevent very short words from cluttering the list.

Double-click a result in the list to copy it to the clipboard, or use menu item Edit->Copy or key combination Command+C.

Checking the Use Large Dictionary checkbox will cause PhoneWords to use a 527,000-word dictionary. This may result in many items in the list, possibly making it hard to find the item you want. The default Small Dictionary has about 122,000 words.