Description of the Co:Writer Extension Dictionaries: 

All Words:

Approximately 40,000 words. For writers who need support for a wide range of words.   Includes highly detailed and precisely descriptive words. 

Core Words: 

Approximately 1,000 words. Limited to basic, high-frequency "function" words, including key descriptors (big, new) and action words (want, make). Includes only a small number of "content" words (such as boy, friend, hand). 

No Words:

No main Dictionary is turned on guesses are predicted from Topic dictionaries that are turned on and from text that is on the page.*

 *(If Predict from Page is turned off guesses will only be predicted from the topic dictionaries you have turned on)