splitword man page
splitwd — Collect several text-form dictionary files into a single file to make a <1 line / 1 word type / 1 candidate> format.
splitwd textjisho ...
If the file in which you registered words consists of several subfiles, it must be converted into a proper format before the word dictionary is created. splitword converts such text-form dictionaries textjisho to make a <1 line / 1 word type / 1 candidate> format. The result is output to the standard output.
% splitwd user1.t user2.t | ctow
Reads text-form dictionaries user1.t and user2.t, then modifies them into the <1 word type, 1 candidate on 1 line> format. The contents are converted into the Wnn textform dictionary, then output to the standard output.