Source: wikibot/meagre-set
= Meagre set
{wiki=Meagre_set}
In the context of mathematical analysis and topology, a **meagre set** (also known as a **first category set**) is a set that can be expressed as a countable union of nowhere dense sets. A set \\( A \\) is said to be nowhere dense in a topological space \\( X \\) if the interior of its closure is empty; that is, there are no open sets in \\( X \\) that contain any points of \\( A \\) in a non-empty way.