Etymology

Old English ancestre, auncestre, also ancessour; the first forms from Old French ancestre, French ancêtre, from the Latin nom. antecessor one who goes before; the last form from Old French ancessor, from Latin acc. antecessorem, from antecedere to go before; ante before + cedere to go. See cede, and compare with antecessor.

Noun

(female ancestress)

1. One from whom a person is descended, whether on the father's or mother's side, at any distance of time; a progenitor; a fore father.
2. (Biology) An earlier type; a progenitor

   This fossil animal is regarded as the ancestor of the horse.

3. (Law) One from whom an estate has descended;—the correlative of heir.