3. The word retrieval device according to claim 1 , further comprising a selector which sets a character string defining a document type, wherein the extractor compares each word obtained from the morphological analysis result with the character string and extracts the word when the word corresponds to the character string.
3. The word retrieval device according to claim 1 , further comprising a selector which sets a character string defining a document type, wherein the extractor compares each word obtained from the morphological analysis result with the character string and extracts the word when the word corresponds to the character string. 4. The word retrieval device according to claim 3 , wherein the character string includes information of notation and a part of speech of the character string, and the extractor compares the notation or the notation and part of speech of each word in the text, with the notation or the notation and part of speech of the character string and extracts a word corresponding to the notation or the notation and part of speech of the character string.