Synonyms for Coalition (same or very similar meaning)
WordNet sense 1 (the state of being combined into one body):
fusion
WordNet sense 2 (an organization of people (or countries) involved in a pact or treaty):
alignment, alliance, alinement
WordNet sense 3 (the union of diverse things into one body or form or group; the growing together of parts):
coalescence, concretion, coalescency, conglutination
From the ODE community, based on WordNet
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