TITLE: Boundedness in a topological space?
QUESTION [6 upvotes]: I was wondering if there is a concept of boundedness for subsets of
a topological space?
If yes to 1, is it this one from Wiki

Elements of a Bornology B on a set X are called bounded sets and the pair (X,
  B) is called a bornological set.
For any topological space X, the set of subsets of X with compact
  closure is a Bornology.

If yes to 2, does it coincide with boundedness in a metric space and in a
topological vector space? How is it related to total boundedness in
a uniform space?

Thanks and regards!

REPLY [3 votes]: To see the relation between boundedness, total boundedness, and kinds of topological spaces, I suggest you consider characterizations of compactness.
An example that helps me here is the one-point compactification of the real line. If we take away the metric, the point at infinity is just like all the other points. So there's no boundedness or unboundedness.

REPLY [2 votes]: The bornology defined in the Wiki article you referenced is normally called a hereditary ideal in set theory, although a hereditary ideal is not required to cover the space. However, as ideals are used to define notions of "smallness", and usually points are "small", all of the widely studied ones I'm aware of do cover the space. Examples are the Lebesgue measure zero subsets of the line, and the meager sets in a topological space. 
An example of a hereditary ideal that doesn't cover the space is the set of $\mu$ measure zero sets where $\mu$ gives at least one point positive measure. 
I've never heard of a hereditary ideal being used to define a notion of boundedness.