1. An information display apparatus comprising: a display section; a dictionary information storage section which stores a plurality of sets of an entry word corresponded to explanatory information of the entry word; a text display control section which displays a text on the display section based on user operation; a character string storage section which stores a character string specified by user operation from among the character string in a text displayed on the display section corresponded with position information showing a position of the character string in the text; a character string list display control section which displays in a list on the display section the character string stored in the character string storage section based on user operation according to position order of the character string in the text; and an explanatory information display control section which reads from a storage content of the dictionary information storage section explanatory information of an entry word corresponding to the character string specified by user operation among the character string displayed by control of the character string list display control section to display the explanatory information on the display section.