With the fact that this is not an encyclopedic reference kept in mind, one can honestly say that this is the best mathematical dictionary available. The book covers every term one might expect to find: from the most elementary topics of the field through a complete undergraduate (and possibly first year graduate) mathematical education. It explains all terms with remarkable detail and clarity, clearing any doubt a reader of math textbooks might have concerning the terms therein contained. Barron's and McGraw-Hill provide very good dictionaries, but lack the clarity of exposition and enourmous scope of this one. Put plainly, I have found this to be an invaluable reference tool far superior to those offered by other publishing companies.