Bible Dictionary
REFUTE
To refute means to convict, expose, or disprove an error. In Jude, the wording is connected with dealing mercifully or correcting those who are in doubt, though the ancient text is uncertain.
Biblical Usage
The Revised Version reads “have mercy” on some who are in doubt, while its margin offers “refute while they dispute.” The alternative means to convict or refute sinful error.