You searched for: “conurbations
conurbation (s) (noun), conurbations (pl)
1. The gradual merging or combination of city areas together: "Some metropolitan planners call conurbation 'one vast megalopolis' ".

"There are more and more neighboring towns around the world that have spread into and blended with each other to form conurbations consisting of highly populated regions with sprawling areas of cities that are clustered together."

2. Etymology: from Latin con-, "together" + urbs, "city" + the English noun suffix -ation, "an action or process".
This entry is located in the following unit: urban- urb-, -urban, -urbia (page 1)