among civilians, implies a relation contracted by marriage, in contradistinction to consanguinity, or relation by blood. Affinity does not found any real kinship; it is no more than a kind of fiction, introduced on account of the close relation between husband and wife. It is even said to cease when the cause of it ceases: hence a woman who is not capable of being a witness for her husband's brother during his lifetime, is allowed for a witness when a widow, by reason the affinity is dissolved. Yet with regard to the contracting of marriage, affinity is not dissolved by death, though it be in every thing else.—There are several degrees of affinity, wherein marriage was prohibited by the law of Moses: thus, the son could not marry his mother, or his father's wife (Lev. xviii. 7. et seq.); the brother could not marry his sister, whether she were so by the father only or by the mother only, and much less if she was his sister both by the same father and mother; the grandfather could not marry his grand-daughter, either by his son or daughter. No one could marry the daughter of his father's wife; nor the sister of his father or mother; nor the uncle his niece; nor the aunt her nephew; nor the nephew the wife of his uncle by the father's side. The father-in-law could not marry his daughter-in-law; nor the brother the wife of his brother while living, nor even after the death of his brother if he left children. If he left no children, the surviving brother was to raise up children to his deceased brother, by marrying his widow. It was forbidden to marry the mother and the daughter at one time, or the daughter of the mother's son, or the daughter of her daughter, or two sisters together.

AFFINITY is also used to denote conformity or agreement. Thus we say, the affinity of languages, the affinity of words, the affinity of sounds, &c.

in Chemistry, a term employed to express that peculiar propensity which the particles of matter have to unite and combine with each other exclusively, or in preference to any other connection.—The attractions between bodies at insensible distances, and which of course are confined to the particles of matter, have been distinguished by the name of affinity; while the term attraction has been more commonly confined to cases of sensible distance.