1.A formal organization of people or groups of people.
2.The act of consorting with or joining with others.
3.The state of being connected together as in memory or imagination.
6.A relation resulting from interaction or dependence. "The host is not always injured by association with a parasite"
7.(chemistry) any process of combination (especially in solution) that depends on relatively weak chemical bonding.
8.(ecology) a group of organisms (plants and animals) that live together in a certain geographical region and constitute a community with a few dominant species.
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