Cosmos and universe are often interchanged, but 'cosmos' is a broader description. For instance there may be more than one universe (multiverse theory) but there is always one cosmos. People may believe in just the one universe - here, 'universe' is synonymous with the 'cosmos'. But for many theorists, the universe is a subset or only part of the greater cosmos.

There isn't one. Seriously. In English, there's a general rule* against using the same word multiple times close together. Instead, writers or speakers will pick a synonym if they need to refer to the same thing. So here, the two words are synonyms. *sometimes, this rule will be deliberately broken. Style is funny that way.

No expert but I'd think firstly that the "universe" includes the physics that keeps it together. There are definitions online that match as Marlon says. I'd suspect that these definitions that say matter, space and energy, are simply written by those who have not thought beyond these elements, but do not intend to exclude other aspects. Just my guess.

Universe is the totality of all the matter in the esistence along with the space, whereas cosmos include the interactive forces and some non-matter things which are abstract in nature. The cosmos is the Universe. Using the word cosmos rather than the word universe implies viewing the universe as a complex and orderly system or entity; the opposite of chaos.

Universe is the totality of all the matter in the esistence along with the space, whereas cosmos include the interactive forces and some non-matter things which are abstract in nature. The cosmos is the Universe. Using the word cosmos rather than the word universe implies viewing the universe as a complex and orderly system or entity; the opposite of chaos.