hyph_en_us.dic

Dictionary file

A .dic file contains a word list for a spell checker or an input method. The content is plain text in most cases, one word for each line. Office applications keep custom words in such files. The Hunspell system pairs a .dic word list with an .aff rule file. Windows input methods also ship binary dictionaries with this extension.

A file extension is only a part of the file name. It does not give a guarantee about the format or the content of a file. But on Windows, the extension selects the program that opens the file.