A fetus is a mammal before it's born. Once upon a time, you started as an embryo, matured into a fetus, and were then thrust into the world as a newborn.

Fetus is a Latin word that means "the bearing, bringing forth, or hatching of young." Even though the Latin points to a fetus "hatching," contemporary science only regards viviparous vertebrates as having fetuses. In other words, if an animal has a backbone and was delivered via live birth, it was once a fetus. If a kitten has claws, whiskers, and ears, but is still inside its mother's womb, it's a fetus. In the UK, fetus is spelled foetus.

Definitions of fetus
  1. noun
    an unborn or unhatched vertebrate in the later stages of development showing the main recognizable features of the mature animal
    synonyms: foetus
    see moresee less
    monster, teras
    (medicine) a grossly malformed and usually nonviable fetus
    a human fetus whose weight is less than 0.5 kilogram when removed or expelled from the mother's body
    an unborn child; a human fetus
    type of:
    craniate, vertebrate
    animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium
Word Family
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