[posterboy]

The concept word is not clearly defined. As a programmer it seems natural to assume that a word is a short series of bits. Anything else is composition. Why is of a word but -ed isn't? ab- is from the same origion, as in aberrant. The difference isn't completely arbitrary. Bio Logy might as well be two wods. The keyword is lexicalization and how words are learned. Obviously, shorter words are easier to discover.