One of the mysteries of the English language finally explained.
Definition of affeeror in English:
affeeror
noun
historicalA person appointed to determine the values of fines and amercements, typically charged with adjusting a generally prescribed penalty according to the particular circumstances of an offender and his or her offence.
Origin
Early 16th century; earliest use found in John Fitzherbert (d. 1531). From Anglo-Norman afferour, affoerour, affirour assessor of amercements from afferer, affoerer, etc. affeer + -our.