[1] : The Collaborative International Dictionary of English v.0.48

fetus \fe"tus\ f=e"tu^s, n.; pl. fetuses
   f=e"tu^se^z. l. fetus, foetus, a bringing forth,
   brood, offspring, young ones, cf. fetus fruitful, fructified,
   that is or was filled with young; akin to e. fawn a deer,
   fecundity, felicity, feminine, female, and prob. to do, or
   according to others, to be.
   the young or embryo of a vertebrate animal in the womb, or in
   the egg; often restricted to the later stages in the
   development of viviparous and oviparous animals. showing the
   main recognizable features of the mature animal, embryo
   being applied to the earlier stages. written also
   foetus.
   1913 webster
see also:
fetuses embryo foetus 

[2] : WordNet (r) 2.0

fetus
     n : an unborn or unhatched vertebrate in the later stages of
         development showing the main recognizable features of the
         mature animal syn: foetus
see also:
foetus 

Fetus >> F Words
Fetus, definition of term: Fetus
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