Definition of one–one

  1. 1 of a relation in logic :  constituted so that if one term is given only one thing can be the other term in a monogamous society the relation “husband-wife” is one-one — compare many-one, one-many

  2. 2 :  one-to-one a one-one correlation between the names of things and the things named — W. E. Johnson

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capable of being understood in two ways

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