How to say "nucleus" in Japanese

• 中堅ちゅうけんCommon
  nounCovers 'nucleus' as the dependable backbone or mainstay of an organization — often the middle-ranking, key figures in a company rather than its top leadership.
• 主体しゅたいJLPT N1approx.Common
  nounUsed for the nucleus as the main constituent or agent around which activity revolves — the party that takes the leading, initiating role rather than a physical core.
• 中核ちゅうかくCommon
  nounThe closest general equivalent for 'nucleus' meaning the core or center of a group, organization, or movement; the most reliable choice for that abstract sense.
• 基幹きかんCommon
  nounMatches 'nucleus' as a mainstay or key element, typically in the sense of something essential that an organization or system depends on, such as its key industries or functions.
• 原子核げんしかくCommon
  nounThis is the strictly scientific term for the nucleus of an atom. For physics or chemistry contexts this is the word you want; it is not used for figurative senses of 'nucleus'.
  原子核げんしかくには大量たいりょうのエネルギーが封じ込ふうじこめられている。↗

  A great deal of energy is locked up in the nucleus.

For the scientific sense choose 原子核; for a central person, group, or institution choose 中核, with 中堅 for the backbone of an organization, 基幹 for key infrastructure, and 主体 for the central agent.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 中堅ちゅうけんnucleus
• 主体しゅたいmain constituent
• 中核ちゅうかくkernel
• 基幹きかんmainstay
• 原子核げんしかくnucleus
• 中枢ちゅうすうcentre
• 細胞核さいぼうかくnucleus
• 推進母体すいしんぼたいnucleus (of a project proposal, of a social movement, etc.)
• ニュクリアスnucleus
• 中心核ちゅうしんかくcore (of planets, stars, galaxies, etc.)
• 核かくcore (of an organization, team, etc.)
• 母体ぼたいparent body
• 心髄しんずいcentre