4. The electronic dictionary apparatus according to claim 3 , further comprising: multi-dictionary search means for searching for the vocabulary entries by switching the dictionary database from which the vocabulary entries including the search characters inputted by user operations are searched in accordance with the user operation, and for list-displaying the searched respective vocabulary entries from the dictionary database on the display; and collective additional search means for searching for vocabulary entries which are the same as the selected vocabulary entry from the other plurality of dictionary databases, and for list-displaying the searched vocabulary entries which are the same as the selected vocabulary entry from the plurality of dictionary databases collectively on the display when the additional search key is operated in a state in which the user has selected one vocabulary entry in the list display of the respective vocabulary entries form one dictionary database searched by the multi-dictionary search means.
4. The electronic dictionary apparatus according to claim 3 , further comprising: multi-dictionary search means for searching for the vocabulary entries by switching the dictionary database from which the vocabulary entries including the search characters inputted by user operations are searched in accordance with the user operation, and for list-displaying the searched respective vocabulary entries from the dictionary database on the display; and collective additional search means for searching for vocabulary entries which are the same as the selected vocabulary entry from the other plurality of dictionary databases, and for list-displaying the searched vocabulary entries which are the same as the selected vocabulary entry from the plurality of dictionary databases collectively on the display when the additional search key is operated in a state in which the user has selected one vocabulary entry in the list display of the respective vocabulary entries form one dictionary database searched by the multi-dictionary search means. 5. The electronic dictionary apparatus according to claim 4 , wherein: the example sentence search means searches for the example sentences by switching the dictionary database from which the example sentences including the search characters inputted by the user operations are searched in accordance with the user operation, and list-displays the searched respective example sentences from the dictionary database on the display.