What is Female?

Legal Definition
Female (♀) is the sex of an organism, or a part of an organism, that produces non-mobile ova (egg cells). Most female mammals, including female humans, have two X chromosomes.
-- Wikipedia
Legal Definition
This term denotes the sex which bears young.

2. It is a general rule, that the young of female animals which belong to us, are ours, nam fetus ventrem sequitur. Inst. 2, 1, 19; Dig. 6, 1, 5, 2. The rule is, in general, the same with regard to slaves; but when a female slave comes into. a free state, even without the consent of her master, and is there delivered of a child, the latter is free. Vide Feminine; Gender; Masculine.
-- Bouviers Law Dictionary
Legal Definition
The sex which conceives and gives birth to young. Also a member of such sex. The term is generic, but may have the specific meaning of "woman," if so indicated by the context. State v. Hemm, 82 Iowa, 609, 48 N. W. 971.
-- Black's Law Dictionary