The difference between Clique and Ingroup

When used as nouns, clique means a small, exclusive group of individuals, whereas ingroup means the social group that one belongs to.

When used as verbs, clique means to associate together in a clannish way, whereas ingroup means to form an ingroup.

check bellow for the other definitions of Clique and Ingroup

Clique as a noun:

A small, exclusive group of individuals; a cabal.

Examples:

"This school used to be really friendly, but now everyone keeps to their own cliques."
Clique as a noun (graph theory):

A subgraph isomorphic to a complete graph.

Examples:

"The problem of finding the largest clique in an arbitrary graph is NP-complete."
Clique as a noun (Internet):

A group of related web sites that link to each other, like a webring but with exclusive membership determined by the clique owner.

Clique as a verb (intransitive):

To associate together in a clannish way; to act with others secretly to gain a desired end; to plot.

Ingroup as a noun (sociology):

The social group that one belongs to.
Ingroup as a noun (systematics):

In cladistics, the monophyletic group that includes all taxa of interest to the current study.