0 a word or phrase that is listed separately with its own definition, examples of use, etc. in a dictionary or similar book:
The syllabication of headwords is not generally an important feature in British dictionaries.
Because of run-on words (like cunningly and cunningness under cunning), a dictionary that claims 150,000 entries may have no more than 80,000 headwords.
There are not as many headwords as one might expect to find in other books of this size.
Entering a word in the Synonym box calls up a list of headwords in alphabetical order.