Fetus

n. young of a human or animal while in the womb or egg

A fetus (or foetus, or fœtus) is a developing mammal or other viviparous vertebrate, after the embryonic stage and before birth. The plural is fetuses (foetuses, fœtuses) or, very rarely, foeti.In humans, the fetal stage of prenatal development begins about eight weeks after fertilization, when the major structures and organ systems have formed, until birth.
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Noun
1. an unborn or unhatched vertebrate in the later stages of development showing the main recognizable features of the mature animal
(synonym) foetus
(hypernym) vertebrate, craniate
(hyponym) monster, teras
(part-meronym) ductus arteriosus

n. fetus, young of a human or animal while in the womb or egg

n. wisp, trace