The present participle of 'clique' when used as a verb; forming or participating in cliques.
From 'clique' (verb form) + '-ing' (present participle suffix). A relatively recent verbal use of the noun 'clique.'
Nouns and verbs are surprisingly fluid in English—we readily turn nouns into verbs ('to clique,' 'to text,' 'to google'), and '-ing' makes them gerunds that describe the action.
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