1.Relationship by marriage (as between a husband and his wife's blood relations, or between a wife and her husband's blood relations); in contradistinction to consanguinity, or relationship by blood; followed by with, to, or between. "Solomon made affinity with Pharaoh."
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."
3.Companionship; acquaintance. (Obs.) "About forty years past, I began a happy affinity with William Cranmer."
4.(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.
5.(Nat. Hist.) A relation between species or higher groups dependent on resemblance in the whole plan of structure, and indicating community of origin.
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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