What is the meaning of Matching?

present participle and gerund of match

The same as another; sharing the same design.

That constitutes part of a pair with something else; complementary.

The process by which things are matched together or paired up.

A set of independent edges in a given graph, i.e. a set of edges which do not intersect, such that pairs of vertices are "matched" to each other one to one.

Source: wiktionary.org