Why is it called "Pro?"

Unfortunately, this dictionary really cannot be called "Pro." One would think that "Pro" means "for the non-novice" or "for those seeking additional definitions for less common words." This dictionary, however, is geared toward beginning students and should market itself as such.

For example, upon download, I immediately attempted to find some words I had recently come across -- to no avail. "Mordiente" -- no entry found. "Verdín" -- no entry found. While these are not words that basic students need to know, a "Pro" dictionary should be exactly that -- more advanced, with a wider range of vocabulary and an eye toward words a student of Spanish will encounter as his or her studies progress.

Spanish literature student about Collins Spanish-English