What does 核 mean?
核 is a Japanese noun meaning “nucleus, kernel” in English. It can also be translated as “nuclear weapons” depending on context. It is written as 核 in kanji, かく in hiragana, and kaku in romaji. This word is part of JLPT N3 vocabulary.
Example sentence
この核時代にあっては、世界中どこの国だって安全ではない。
No country under the sun is safe in this nuclear age.