A word is defined by it's popular use.
By Seth russell .. revised 7/3/2002

@@ indicate where work needs to be done and the concept or termonology needs more work.

The denotion (meaning or definition) of a word is a mathematical relationship between the word and an object in some domain to some agent.  This is expressed by the formula:
{"W" refersTo R} :to: B :in: L            @@@  find the correct formula
                                                              @@@ provide a mentograph
seeUrl http://www.earlham.edu/~peters/writing/logicsym.htm
In the case of a formal language, B is the corpora of well formed formulas in the language L.  In the case of a natuarl language, B is the corpora of usages of of the word "A" by the members of a class of (usually human) agents.  The former case is a special case of the latter.  

The major point I am raising is that  agents (even in the same class) may have different (denotations, meanings, referants, meanings, definitions) of the same word, and\or may use different words to denote that same object. Consequently the (meaning , denotition, reference) of the word in the language L is a (stastical relationship).   I am calling this (statistical relationship) popular use.  This (stastical relationship) is similar to the  (stastical relationship) between a key word typed into googleand the top site returned by that search engine; because google employs 'popular use' to determing the site to return on the top of it's list.   @@ more math here to prove the similarity of of these mathematical functions @@

Words, so defined by popular use, are more ambiguous than those define by the precision of reference of a formal  language, yet are more useful over a larger domain and society.  Witness how frequently your peers understand what hyou are talking about.  

Now lets compare and contrast the definition of a word in a formal language, to the definition of a word found on the first hit at google.   .... which kind of definiton fits in with the semantic web ?