Metro Toronto

Short definition from Wiktionary

Proper noun

1. 1
   A former supramunicipal government that existed in the late 20th century, composed of the former cities of Etobicoke, Scarborough, York, North York, East York, Toronto; which was merged into the 21st century city of Toronto, with six boroughs composed of the former cities of the merger.
2. 2
   The GTA; Synonym of Greater Toronto Area (“Greater Toronto”) (metropolitan Toronto) (metropolitan Toronto area)