核心

1. Origins, structure, and basic meaning

• Structure: The spelling is 核心, read かくしん, and it combines 核, meaning core, with 心, meaning heart or center.
• Basic usage: The basic sense of 核心 is the core or most important central part of an issue, discussion, or object.

2. Common pitfalls and similar expressions

• Going to the heart and addressing the core
  • Both examples use the form 核心. 核心を突く means identifying the most important point precisely, while 核心に触れる means addressing that central content.
• A precise question and a wandering explanation
  • 彼の質問は議論の核心を突いていた。 — His question went to the heart of the discussion.
  • 説明が長く、なかなか問題の核心に触れない。 — The explanation is long and does not readily address the core of the problem.