Shrievalty, “the office, term, or jurisdiction of a sheriff,” is a rare word. Shrieve is one of many, many spelling variants of the Late Middle English compound noun shire-reeve. A shire is “the office of administration, jurisdiction of an office or county,” and a reeve is “a high official in charge of an administrative district.” Sheriff is an ordinary outcome of shire-reeve. The suffix -alty is taken from such political and legal terms as mayoralty (from mayoral and the suffix -ty, from Old French -tet, ultimately from Latin -tās, a suffix for forming abstract nouns from adjectives). The equally rare but more transparent noun sheriffalty was also formed from sheriff and -alty. Shrievalty entered English in the 16th century.