fetus, foetus

an unborn or unhatched vertebrate in the later stages of development showing the main recognizable features of the mature animal

• 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

• vertebrate, craniate — animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium

• ductus arteriosus — a blood vessel in a fetus that bypasses pulmonary circulation by connecting the pulmonary artery directly to the ascending aorta; normally closes at birth
• umbilical cord — membranous duct connecting the fetus with the placenta