1. an unborn human baby more than eight weeks after conception
Usage: medical
2. an unborn or unhatched vertebrate animal in the later stages of development
Usage: biology

Examples

• The ultrasound showed a healthy fetus at 20 weeks.
• Doctors monitor fetal development throughout pregnancy.
• The fetus begins to move around the fourth month.
• Prenatal vitamins help support fetus growth.
• Scientists studied fetal brain development in mammals.
• The veterinarian examined the fetus through ultrasound.