核兵器（かくへいき、kakuheiki）
- nuclear weapons

The Japanese word 核兵器 核兵器 (かくへいき - *kaku heiki*) directly translates to "nuclear weapon" or "atomic weapon." It refers to weapons that derive their destructive power from nuclear reactions, either nuclear fission or nuclear fusion. These weapons are known for their immense explosive yield and devastating effects. They are also known as weapons of mass destruction. ⚫︎ Nuclear weapons are characterized by their ability to cause widespread destruction, including massive explosions, intense heat, ionizing radiation, and long-term environmental contamination. ⚫︎ The use and proliferation of nuclear weapons are subjects of significant international concern and are regulated by treaties and agreements.

⚫︎核兵器の廃絶を目指しています。 Translation: We are aiming for the abolition of nuclear weapons. ⚫︎その国は核兵器を開発する能力を持っています。 Translation: That country has the capability to develop nuclear weapons. ⚫︎核兵器の使用は世界的な脅威です。 Translation: The use of nuclear weapons is a global threat.

核兵器 核兵器 is used in formal and informal contexts. It's a general term applicable in discussions about international relations, military strategy, history, or any other area where nuclear weapons are relevant. ⚫︎ The word is usually used in discussions about war, peace, disarmament, international politics, and the dangers posed by nuclear armaments. ⚫︎ It is always written in kanji when used in formal or written Japanese, or very very rarely in katakana.

⚫︎ The word 核兵器 核兵器 is most commonly written using the kanji 核 (*kaku*, nucleus) and 兵器 (*heiki*, weapon). ⚫︎ The reading, かくへいき, is written in hiragana. ⚫︎ There are no significant variations in okurigana.

There aren't direct synonyms in Japanese, but related terms include: ⚫︎ 原子爆弾 (*genshi bakudan*) - atomic bomb. ⚫︎ 原爆 (*genbaku*) - abbreviation of 原子爆弾, often used informally, and used in association with 広島 and 長崎. ⚫︎ 大量破壊兵器 (*tairyou hakai heiki*) - weapons of mass destruction (this is a broader term that includes chemical and biological weapons as well).

There aren't direct antonyms, but the opposite concept would be related to: ⚫︎ 平和 (*heiwa*) - peace. ⚫︎ 軍縮 (*gunshuku*) - arms control/disarmament. ⚫︎ 非核 (*hikaku*) - non-nuclear. ⚫︎ 通常兵器 (*tsuujou heiki*) - conventional weapons.

世界は核兵器の拡散を防ぐために努力している。 ・Translation: The world is working to prevent the spread of nuclear weapons. ・Explanation: This sentence discusses international efforts to limit the proliferation of nuclear weapons, highlighting a significant concern.

日本は非核三原則を堅持している。 ・Translation: Japan adheres to the Three Non-Nuclear Principles. ・Explanation: This sentence refers to Japan's policy of not possessing, manufacturing, or permitting the introduction of nuclear weapons into its territory.

The word 核兵器 核兵器 is a compound word. ⚫︎ 核 (*kaku*) comes from the Chinese word for “nucleus” and refers to the central part of the atom, which is essential for nuclear reactions. ⚫︎ 兵器 (*heiki*) translates to “weapon” or "arms". Together, they form a compound word to refer to "nuclear weapons."