Standard Lemma guide

neptunium

noun · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • nĕptū'nēəm
  • /nɛpˈtjuːniəm/
  • nĕpto͞o'nēəm
  • /nɛpˈtuːniəm/
  • Southern-England: Recorded audio is listed in the source snapshot.
  • General-American: Recorded audio is listed in the source snapshot.
  • CMU ARPABET: N EH0 P T UW1 N IY0 AH0 M Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.

1

noun

Meaning 1

The transuranic chemical element with atomic number 93 and symbol Np.

Definition source: English Wiktionary via Wiktextract

Usage: uncountable

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

a radioactive transuranic metallic element; found in trace amounts in uranium ores; a by-product of the production of plutonium

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: Np, atomic number 93

Antonyms: none provided

Broader terms: metallic element, metal

History

Etymology

From Neptune + -ium, after the planet. The previous element is uranium, named after the previous planet: Uranus.

Across languages

Translations

70 source translations are retained for this English entry.

  • Afrikaans: neptunium — chemical element
  • Albanian: neptun — chemical element
  • Arabic: نِبْتُونِيُوم (nibtūniyūm) — chemical element
  • Armenian: նեպտունիում (neptunium) — chemical element
  • Asturian: neptuniu — chemical element
  • Basque: neptunioa — chemical element
  • Belarusian: непту́ній (njeptúnij) — chemical element
  • Breton: neptuniom — chemical element
  • Bulgarian: непту́ний (neptúnij) — chemical element
  • Catalan: neptuni — chemical element
  • Chinese Mandarin: 镎 (ná) — chemical element
  • Cornish: neptunyum — chemical element
  • Czech: neptunium — chemical element
  • Danish: neptunium — chemical element
  • Dutch: neptunium — chemical element
  • Esperanto: neptunio — chemical element
  • Estonian: neptuunium — chemical element
  • Faroese: neptunium — chemical element
  • Finnish: neptunium — chemical element
  • French: neptunium — chemical element
  • West-Frisian: neptunium — chemical element
  • Friulian: netuni — chemical element
  • Galician: neptunio — chemical element
  • Georgian: ნეპტუნიუმი (neṗṭuniumi) — chemical element
  • German: Neptunium — chemical element
  • Greek: ποσειδώνιο (poseidónio) — chemical element
  • Hebrew: נפטוניום (neptúnyum) — chemical element
  • Hungarian: neptúnium — chemical element
  • Icelandic: neptún — chemical element
  • Icelandic: neptúnín — chemical element
  • Irish: neiptiúiniam — chemical element
  • Italian: nettunio — chemical element
  • Japanese: ネプツニウム (neputsuniumu) — chemical element
  • Kashubian: neptun — chemical element
  • Korean: 넵투늄 (neptunyum) — chemical element
  • Latin: neptunium — chemical element
  • Latvian: neptūnijs — chemical element
  • Lithuanian: neptūnas — chemical element
  • Luxembourgish: Neptunium — chemical element
  • Macedonian: нептуниум (neptunium) — chemical element
  • Malay: neptunium — chemical element
  • Maltese: neptunjum — chemical element
  • Manx: nepçhunium — chemical element
  • Mongolian: нептуни (neptuni) — chemical element
  • Norwegian Bokmål: neptunium — chemical element
  • Norwegian Nynorsk: neptunium — chemical element
  • Polish: neptun — chemical element
  • Portuguese: neptúnio — chemical element
  • Romanian: neptuniu — chemical element
  • Russian: непту́ний (neptúnij) — chemical element
  • Scottish Gaelic: neiptiùiniam — chemical element
  • Serbo-Croatian: нептуниj — chemical element
  • Serbo-Croatian: нептуниjум — chemical element
  • Serbo-Croatian: neptunij — chemical element
  • Serbo-Croatian: neptunijum — chemical element
  • Slovak: neptunium — chemical element
  • Slovene: neptunij — chemical element
  • Spanish: neptunio — chemical element
  • Swedish: neptunium — chemical element
  • Tajik: нептуний (neptuniy) — chemical element
  • Tamil: நெருப்பியம் (neruppiyam) — chemical element
  • Thai: เนปทูเนียม (néep-tuu-nîiam) — chemical element
  • Turkish: neptünyum — chemical element
  • Ukrainian: непту́ній (neptúnij) — chemical element
  • Uzbek: neptuniy — chemical element
  • Uzbek: нептуний (neptuniy) — chemical element
  • Vietnamese: neptuni — chemical element
  • Volapük: neptunin — chemical element
  • Welsh: neptwniwm — chemical element
  • Yiddish: נעפּטוניום (neptunyum) — chemical element