decree [ME] Early decrees were edicts issued by an ecclesiastical council to settle a point of doctrine or discipline. The word is from Old French decre, from Latin decretum ‘something decided’, from decernere ‘decide’. The nisi in the term decree nisi (late 19th century) is the Latin word for ‘unless’; the phrase represents a court order stating when a marriage will end ‘unless’ a good reason to prevent divorce is produced.