n. - The act of giving premature birth; particularly, the expulsion of the human fetus prematurely, or before it is capable of sustaining life; miscarriage.
n. - The immature product of an untimely birth.
n. - Arrest of development of any organ, so that it remains an imperfect formation or is absorbed.
n. - Any fruit or produce that does not come to maturity, or anything which in its progress, before it is matured or perfect; a complete failure; as, his attempt proved an abortion.