How and why did neighborhoods start being referred to as Wards, e.g. 9th Ward?

Question

Is it an official term or something that residents started?

Answer 1

This was a common way to divide cities during the 18th and 19th centuries before we had the modern city council district and precinct system. In the old days, each ward had an alderman who served on the city council. Many cities still have their older neighborhoods known by their former ward names - like Houston and New Orleans.

Answer 2

New Orleans is divided into voting districts known as wards, which are further divided into precincts. The 9th Ward includes several neighborhoods. The "lower 9th Ward" is separated from the "upper 9th Ward" by the Industrial Canal, which connects Lake Pontchartrain and the Mississippi River through a system of locks.