One of a number of things allied in origin or nature.

(linguistics) A word either descended from the same base word of the same ancestor language as the given word, or strongly believed to be a regular reflex of the same reconstructed root of proto-language as the given word.

(law) Allied by blood; kindred by birth; specifically related on the mother's side.

Of the same or a similar nature; of the same family; proceeding from the same stock or root.

(linguistics) Descended from the same source lexemes (same etymons) of an ancestor language.