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Synonyms for Affinity (same or very similar meaning)

WordNet sense 1 ((biology) state of relationship between organisms or groups of organisms resulting in resemblance in structure or structural parts):
phylogenetic relation

WordNet sense 2 (a close connection marked by community of interests or similarity in nature or character):

WordNet sense 3 (the force attracting atoms to each other and binding them together in a molecule):
chemical attraction

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