One who refuses to take an oath, as of allegiance.
A beneficed Anglican clergyman who refused to swear allegiance to William and Mary and their successors after the Glorious Revolution of 1688.
Any of the clergymen of the Church of England who refused to take an oath of allegiance at the accession of William and Mary in 1689
Origin of nonjuror
non– juror one who takes an oath (obsolete)