Final answer:
A woman who has never given birth is termed nulliparous(a) in the field of biology, differing from primiparous (given birth once) and multiparous (given birth two or more times).
Step-by-step explanation:
A woman that has never given birth is said to be nulliparous(a). This term is used in medicine and biology to describe a female who has not carried a pregnancy beyond 20 weeks of gestation, which is the point at which a fetus is generally considered to be viable outside the womb. This is in contrast to other terms such as primiparous, which refers to a woman who has given birth once, and multiparous, which refers to a woman who has given birth two or more times.