What does "analogy" mean?

Analogy: (Biol.) A relation or correspondence in function, between organs or parts which are decidedly different.

Additional senses

  1. 2.(Geom.) Proportion; equality of ratios.
  2. 3.(Gram.) Conformity of words to the genius, structure, or general rules of a language; similarity of origin, inflection, or principle of pronunciation, and the like, as opposed to pl. analogies. Johnson.

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