fetus
/ˈfiːtəs/noun
fetus is spelled F-E-T-U-S: 5 letters and 2 syllables. It appears 4.0 times per million words in written English, the 12,940th most frequent word form (wordfreq, 2021 data). People search “fetus vs foetus” about 70 times a month (Google, United States). As a noun, fetus means “An unborn or unhatched vertebrate showing signs of the mature animal” (English Wiktionary, September 2026). The plural of fetus is fetuses or fetii; Wiktionary also lists feti (hypercorrect).
How many letters and syllables are in fetus?
| Letters | 5: F-E-T-U-S |
|---|---|
| Syllables | 2 (from its American pronunciation) |
| In writing | 4.0 times per million words; the 12,940th most frequent word form |
| Wrong spellings searched | none measured in search |
| Pairs people search |
Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation and the CMU Pronouncing Dictionary; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media); Bing searches in the United States: the average month from September 2025 to August 2026 (Microsoft Advertising keyword data through DataForSEO, read September 30, 2026).
How common is fetus?
Fetus appears 4.0 times per million words in written English, the 12,940th most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How do you pronounce fetus?
- /ˈfiːtəs/
Fetus has 2 syllables (counted from its American pronunciation in the CMU Pronouncing Dictionary).
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: LL-Q1860_(eng)-Vealhurl-foetus.wav, Wikimedia Commons (author and licence on each file's page).
Words people confuse with fetus
Word pairs people search, with the monthly searches for “a vs b” (G: Google, B: Bing, United States).
Also written: foetus.
Sources: Google and Bing searches (September 2025 to August 2026, through DataForSEO); English Wiktionary (homophones, alternative spellings).
Forms of fetus
- fetuses plural
- feti hypercorrect, plural
- fetii plural
- foetus
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does fetus mean?
The meanings the English Wiktionary records, quoted as written there (source below).
noun
- 1
AustraliaCanadaUSAn unborn or unhatched vertebrate showing signs of the mature animal.
Several feti were removed from every rats' uterus, stripped of their membranes and allowed to lie in the peritoneal cavity connected to the placenta by the umbilical cord and with the placenta still attached to the uterine wall.
- 2
AustraliaCanadaUSA human embryo after the eighth week of gestation.
The sequence is: molecules in reproductive systems, then gametes, zygotes, morulas, blastocysts, and then fetuses.
- 3
AustraliaCanadaUSarchaicA neonate.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Fetus in Spanish, French, German and Portuguese
In the sense an unborn or unhatched vertebrate showing signs of the mature animal:
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.
Where does fetus come from?
A learned borrowing from Latin fētus (“offspring”). Doublet of fawn.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).