fetus

/ˈfidəs/

/ˈfitɪs/

Other forms: fetuses

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

   types:

   monster, teras

   (medicine) a grossly malformed and usually nonviable fetus

   abortus

   a human fetus whose weight is less than 0.5 kilogram when removed or expelled from the mother's body

   baby

   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