Ecumenopolis (from , meaning "world", and πόλις polis meaning "city"), thus a city made of the whole world; pl. ecumenopolises or ecumenopoleis) is the hypothetical concept of a planet wide city. The word was invented in 1967 by the Greek city planner Constantinos Doxiadis to represent the idea that in the future urban areas and megalopolies would eventually fuse and there would be a single continuous worldwide city as a progression from the current urbanization and population growth trends. This concept was already current in science fiction in 1942, with Trantor in the Foundation series.

Ecumenopolis (from , meaning "world", and πόλις polis meaning "city"), thus a city made of the whole world; pl. ecumenopolises or ecumenopoleis) is the hypothetical concept of a planet wide city. The word was invented in 1967 by the Greek city planner Constantinos Doxiadis to represent the idea that in the future urban areas and megalopolies would eventually fuse and there would be a single continuous worldwide city as a progression from the current urbanization and population growth trends. This concept was already current in science fiction in 1942, with Trantor in the Foundation series.