neptunium
/nɛpˈtjuːniəm/noun
neptunium is a noun meaning “The transuranic chemical element with atomic number 93 and symbol Np” (English Wiktionary, September 2026). It is spelled N-E-P-T-U-N-I-U-M and has 4 syllables, and it appears about once in every 17 million words in written English (wordfreq, 2021 data).
What does neptunium mean?
noun
- 1
The transuranic chemical element with atomic number 93 and symbol Np.
- 2
An atom of this element.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How do you pronounce neptunium?
- /nɛpˈtjuːniəm/
- /nɛpˈtuːniəm/
Neptunium has 4 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-neptunium.wav, LL-Q1860_(eng)-Naomi_Persephone_Amethyst_(NaomiAmethyst)-neptunium.wav, Wikimedia Commons (author and licence on each file's page).
How common is neptunium?
Neptunium appears about once in every 17 million words in written English, the 124,184th 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).
Neptunium in Spanish, French, German and Portuguese
In the sense chemical 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.