Middle English (originally denoting a heretic, specifically an Albigensian): from Middle Dutch, from Old French bougre 'heretic', from medieval Latin Bulgarus 'Bulgarian', particularly one belonging to the Orthodox Church and therefore regarded as a heretic by the Roman Church. The sense 'sodomite' (16th century) arose from an association of heresy with forbidden sexual practices; its use as a general insult dates from the early 18th century.

• A bugger was originally a heretic—this was the meaning of Old French bougre. The word ultimately comes from Bulgarus, which was the Latin term for a Bulgarian, in particular one who belonged to the Orthodox Church, which was regarded by the Roman Catholic Church as heretical. Bugger was first used in English in reference to members of a heretical Christian sect based in Albi in southern France in the 12th and 13th centuries, the Albigensians. The sexual use of the term arose in the 16th century from an association of heresy with forbidden sexual practices.