🔍 Definition & Meaning:
A fetus (noun) /ˈfiː.təs/ is the developing human (or mammal) from the end of the embryonic period (around week 9 of pregnancy) until birth. During this stage, organs and body systems mature and prepare for life outside the womb.
🔹 Pronunciation:
/ˈfiː.təs/
(“FEE-tus”)
🔹 Grammatical Formation:
- Noun (countable):
- The doctors saw the fetus moving on the ultrasound.
- No common adjective or verb derived directly from “fetus”; use “fetal” for the adjective.
🔹 Simple Explanation (for learners):
A fetus is a baby-in‑the‑womb after about two months of development, when its basic shape is recognizable. Before that, it’s called an embryo. After birth, it’s called a newborn or infant.
🔹 Real‑Life Examples:
- During the second trimester, the fetus grows fingernails and hair.
- Fetal heartbeat can often be detected by week 12.
- Prenatal vitamins support healthy fetal development.
🔹 Common Collocations:
- fetal development
- fetal heartbeat
- fetal movement
- fetal alcohol syndrome
- fetal monitoring
- first‑trimester fetus
- healthy fetus
- fetal surgery
🔹 Idiomatic Usage & Expressions:
There are no standard idioms with “fetus.” However, “fetal stage” or “fetal position” (curling up in a protective posture) appear in figurative speech:
- After the accident, he curled into the fetal position.
🔹 Prepositions & Contextual Uses:
| Phrase | Meaning |
|---|---|
| fetus in utero | The fetus in utero receives nutrients via the placenta. |
| growth of the fetus | Ultrasound measures growth of the fetus weekly. |
| monitoring during fetal stage | They used Doppler for monitoring during the fetal stage. |
| risks to the fetus | Smoking poses serious risks to the fetus. |
🔹 Word Comparison Table:
| Term | Meaning | Context |
|---|---|---|
| Zygote | Single‑cell stage right after fertilization | Biology |
| Embryo | Developing organism until week 8 | Biology |
| Fetus | Developing from week 9 until birth | Biology/Reproduction |
| Newborn | Baby immediately after birth | Pediatrics |
🔹 Synonyms (noun):
unborn child, baby (in utero), conceptus
🔹 Antonyms (noun):
newborn, infant, toddler, adult
🔹 Related Terms:
gestation, placenta, umbilical cord, trimester, prenatal, obstetrics, fetal medicine, prenatal ultrasound, fetal development, congenital
🔹 Connection to Sexuality:
While “fetus” itself is an anatomical/reproductive term rather than a sexual one, it is directly tied to human reproduction, a result of sexual intercourse or assisted reproductive techniques. Discussions of fetal health often appear in sexual and reproductive health contexts.