sheriff: [OE] A sheriff is etymologically a ‘shirereeve’ – that is, a ‘county official’. The term was compounded in the Old English period from scīr, ancestor of modern English shire, and gerēfa ‘local official’, a word based on *rōf ‘assembly’ which survives as the historical term reeve. It was used for the ‘monarch’s representative in a county’. => reeve, shire[sheriff etymology, sheriff origin, 英语词源]