A nut with a built in washer like flange. Tee. A nut designed to be driven into wood to create a threaded hole. Square. A four sided nut. Prevailing torque lock. A non-reversible lock nut used for high temperature applications. K-Lock or Kep. A nut with an attached free-spinning external tooth lockwasher.
adjective. The definition of metropolitan is a city or something related to a city. A city and the immediate locations surrounding it is an example of a metropolitan area.
Metropolitan Statistical Area (MSA) A Metropolitan Statistical Area (MSA) is a designation the U.S. government uses to refer to a region that, broadly speaking, consists of a city and its suburbs, plus any surrounding communities that are closely linked to the city because of social and/or economical factors.