phosphorus
/ˈfɑs.fɚ.əs/noun
phosphorus is spelled P-H-O-S-P-H-O-R-U-S: 10 letters and 3 syllables. It appears 1.8 times per million words in written English, the 20,906th most frequent word form (wordfreq, 2021 data, counting Phosphorus, the name). People search “phosphorous vs phosphorus” about 260 times a month (Google, United States). As a noun, phosphorus means “A chemical element (symbol P) with an atomic number of 15, that exists in several allotropic forms” (English Wiktionary, September 2026). The plural of phosphorus is phosphoruses or phosphori.
How many letters and syllables are in phosphorus?
| Letters | 10: P-H-O-S-P-H-O-R-U-S |
|---|---|
| Syllables | 3 (from its American pronunciation) |
| In writing | 1.8 times per million words; the 20,906th 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 phosphorus?
Phosphorus appears 1.8 times per million words in written English, the 20,906th most frequent word form in the list. The list counts every capitalisation together, so this includes Phosphorus, the name.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How do you pronounce phosphorus?
- UK /ˈfɒs.fə.ɹəs/
- UK /ˈfɒs.fɹəs/
- US /ˈfɑs.fɚ.əs/
Phosphorus has 3 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)-Naomi_Persephone_Amethyst_(NaomiAmethyst)-phosphorus.wav, En-us-phosphorus.ogg, LL-Q1860_(eng)-Tesco250-phosphorus.wav, Wikimedia Commons (author and licence on each file's page).
Words people confuse with phosphorus
Word pairs people search, with the monthly searches for “a vs b” (G: Google, B: Bing, United States).
Sources: Google and Bing searches (September 2025 to August 2026, through DataForSEO); English Wiktionary (homophones, alternative spellings).
Forms of phosphorus
- phosphoruses plural
- phosphori plural
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does phosphorus mean?
The meanings the English Wiktionary records, quoted as written there (source below).
noun
- 1
A chemical element (symbol P) with an atomic number of 15, that exists in several allotropic forms.
For quotations using this term, see Citations:phosphorus.
- 2
An atom of this element.
- 3
obsoleteAny substance exhibiting phosphorescence; a phosphor.
For quotations using this term, see Citations:phosphorus.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How do you abbreviate phosphorus?
Wiktionary records one abbreviation of phosphorus: phos.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Phosphorus in Spanish, French, German and Portuguese
In the sense element:
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.