What does "affinity" mean?

Affinity: 2. Kinship generally; close agreement; relation; conformity; resemblance; connection; as, the affinity of sounds, of colors, or of languages. There is a close affinity between imposture and credulity. Sir G. C. Lewis.

Additional senses

  1. 2.Companionship; acquaintance. [Obs.] About forty years past, I began a happy affinity with William Cranmer. Burton.
  2. 3.(Chem.) That attraction which takes place, at an insensible distance, between the heterogeneous particles of bodies, and unites them to form chemical compounds; chemism; chemical or elective affinity or attraction.
  3. 4.(Nat. Hist.) A relation between species or highe 6. (Spiritualism) A superior spiritual relationship or attraction held to exist sometimes between persons, esp. persons of the opposite sex; also, the man or woman who exerts such psychical or spiritual attraction.

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