Where does the phrase That's not my bailey wick come from?

Answer 1

A bailiwick /ˈeɪlɨwɪk/ is usually the area of jurisdiction of a bailiff, and once also applied to territories in which a privately appointed bailiff exercised the sheriff's functions under a royal or imperial writ. The word is now more generally used in a metaphorical sense, to indicate a sphere of authority, experience, activity, study, or interest. A bailiwick (German:"Ballei") was also the territorial division of the Teutonic Order. Here, various "Komtur(en)" formed a Ballei province.

The term survives in administrative usage in the British Crown dependencies of the Channel Islands, which are grouped for administrative purposes into two bailiwicks-Jersey (comprising the island of Jersey and uninhabited islets such as the Minquiers and Écréhous) and Guernsey (comprising the islands of Guernsey, Sark, Alderney, Brecqhou, Herm,Jethou and Lihou). A Bailiff heads each Channel Island bailiwick.

Answer 2

The phrase "That's not my bailiwick" originates from the late 16th century and means something that is not within one's area of expertise or responsibility. The term "bailiwick" historically referred to a bailiff's jurisdiction or authority.