"dom" is no longer used, but it appears to be very similar to "asser", which is "Role Preference" or whether the slave prefers to be the giver(higher) or taker(lower) of sexual actions.
I use Notepad++ to search multiple files, but it will probably have the same issues. I recommend searching for ".dom", ".dom ", or "var dom" rather than "dom" as the additional context will remove a lot of irrelevant entries.