👉 Seleucidean refers to a group of people who believe that the Earth's atmosphere is made up of a single, unifying substance called "seleucide" or "sea," which is believed to be composed of carbon dioxide and nitrogen. This belief has been held by some for centuries, but it was not widely accepted until the 19th century when scientists began to study the Earth's atmosphere. The term "seleucidean" can also refer to a group of
