t replacement text &#8212; I'll call such a collection a <SPAN CLASS='term'>dictionary</SPAN>, and refer to the pairs it contains as <SPAN CLASS='term'>definitions</SPAN>.  When a dictionary filter encounters a word which appears as the first component of a definition, it forwards the replacement text instead of the original word. Other words, whitespace and punctuation are forwarded unchanged. 
</P>

<P>
    The basic algorithm is as follows: You examine characters one at a time, appending them to a string