1. A computer-implemented method executed by one or more computing devices for building a dynamic classification dictionary, the method comprising: extracting, by at least one of the one or more computing devices, one or more terms from information that characterizes a document; applying, by at least one of the one or more computing devices, a first pattern matching rule to the one or more terms to identify one or more taxonomic nouns in the one or more terms, the first pattern matching rule including comparing sequences of consecutive words in the document with known terms and, if a match exists, merging matching consecutive words into a multi-word term and, if a match does not exist, assigning a single word term as the one or more taxonomic nouns; applying, by at least one of the one or more computing devices, a second pattern matching rule to the one or more terms to determine at least one of a part-of-speech and a noun type associated with at least one taxonomic noun of the one or more taxonomic nouns, the second pattern matching rule being different from the first pattern matching rule; and building, by at least one of the one or more computing devices, a dynamic classification dictionary based on the one or more taxonomic nouns and at least one of the part-of-speech and noun type associated with the at least one taxonomic noun.