PURPOSE: To easily and surely perform retrieval and edition for the variance of a loan word description by providing an original spelling of loan words corresponding to the words in an entity dictionary and a variation table having a KATAKANA (the square form of the Japanese syllabary) system description for each variation of the description.

CONSTITUTION: A variation table 2 is a table having the same record number as each word in an entity dictionary 1, plural descriptions of different words having the same substance, and its original spelling when the word is a loan word written in the KATAKANA description. A description index 3 is a dictionary having the same description as the one to be registered in the variation table, learning information and a link pointer. For example, in the case of 'active', both 'akuchibu' and 'akutibu' written in the KATAKANA description are preserved. For the retrieval request with the KATAKANA system input given, the one having the same description is retrieved by referring to a description index 3 and the variation table 2 is extracted from the link pointer of the retrieved description. Retrieval object word data are read out from the corresponding dictionary 1. When no description is retrieved, the retrieval is performed based on the original spelling.