If you would like a definition of the last word in the message area choose Cmd > Define.
It will be looked up in the Webster's Dictionary 1913 edition. This dictionary was gotten from the Gutenberg Project at gutenberg.org and is in the public domain. One might think it rather dated, but in truth, the language has not changed that much. If the word was found, a window is displayed with the definition. If the text of the definition is lengthy you can scroll Up and Down. You can hear how the word sounds with Speak. Define words within the definition with Define. Close the definition window with Close.
If there is no definition for the word it may have been misspelled. You will be shown some suggested respellings: For example, defining 'DIFICULT' will offer these words:
The suggested words come from www.m-w.com. You can choose one of these to replace 'DIFICULT'.
If the word is correctly spelled but does not appear in Webster's 1913 (like the words e-mail, radio, tofu or microwave) the dictionary at wordwebonline.com will be consulted. Since this involves making a web request there may be a slight delay.
If you would like to force the use of the more modern dictionary append (temporarily) a percent '%' to the word before asking for the definition.
If the word you are asking about ends with an asterisk:
then you will be shown words in the 1913 dictionary that begin with 'RHY' like this:
Again, you can choose one to replace 'RHY*'.
When in Browse mode, there is also a Define command available. If you are reading along and there is a word you are unsure of, choose Define. The cursor will change to a question mark and you will enter 'define mode'. Move the little question mark over the word in question and hover there (or click if in Click mode). The definition of the word under the cursor will be shown. Note that you must pause over the word in question and then move a little bit. This is a little odd but since you get no definition until you DO move you will quickly learn what is needed. Also note that only words of at least 4 characters will be chosen for defining in this manner. This was done to avoid inadvertently choosing a small word in the text.
If the word you are looking up is 'QUICKLY' the 'LY' suffix will be trimmed and the definition for 'QUICK' included as well. These suffixes are used: s, ly, ed, ing, es, ness.
If you chose Define by mistake choose it again to cancel.