n.; pl.Fetuses [ 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 fœtus. ] [ 1913 Webster ]
[卵黄囊 / 卵黃囊, luǎn huáng náng, ㄌㄨㄢˇ ㄏㄨㄤˊ ㄋㄤˊ]yolk sac (ectodermal cells attaching fetus to uterus before the development of the placenta)#88546[Add to Longdo]
[溶血病, róng xuè bìng, ㄖㄨㄥˊ ㄒㄩㄝˋ ㄅㄧㄥˋ]hemolytic disease of newborn (breakdown of red blood cells due to alloimmune reaction between mother and fetus)[Add to Longdo]