Af-fin'i-ty, n.

n. [Lat. affinitas, Fr. affinité, Pr. affinitat, It. affinita, Sp. afinidad, from Lat. affinis. See supra.] 1. Relationship by marriage, in contradistinction from consanguinity, or relationship by blood. Wharton. Burrill. Solomon made affinity with Pharaoh. 1 Kings iii. 1.

2. Close agreement; relation; conformity; resemblance; connection; as, the affinity of sounds, or colors, or of languages.
3. Intercourse; acquaintance. [Obs.]

About forty years past, I began a happy affinity with William Cranmer. Barton.

4. (Chem.) That attraction which takes place, at an insensible distance, between the heterogeneous particles of bodies, and forms compounds.
5. (Nat. Hist.) A relation dependent on resemblance in the whole plan of structure, and making a kinship of species or group; thus distinct from analogy, which is functional correspondence in species, however distinct in affinity, and homology, which is structural correspondence in general features merely. Dana.