Some words with 'round' in them are:
"round" is used to describe the "circle". "circles" is the noun and "round" is an adjective.
swiveled round
"The ball is round"
round or usually round
Round is a root word. Around, roundabout, roundtable, rounding, surround
How can you use the word round in a sentence as a noun
Something which goes round and round.
Round and round, you can make these words:dodondourduononodnoronorourrodrunundourn
In the sentence given, "round" is a noun.
The word you are looking for is "round."
The word world does not imply that that the world is round. Google Earth shows that the world is round lol but seriously everyone knows the world is round.
It is a noun, it means one of a series.