鍵穴

1. Origins, structure, and basic meaning

• Structure: 鍵穴 is a noun read かぎあな, meaning the keyhole in a door or lock.
• Basic usage: It can identify a hard-to-see location or the opening into which a key is inserted.
  • 暗くて鍵穴の位置がよく見えません。 says that it is too dark to see the keyhole's position clearly; 古い扉の鍵穴に鍵を差し込みました。 describes inserting a key into the old door's keyhole.

2. Common pitfalls and similar expressions

• 鍵穴の位置
  • の links the difficult-to-see position to the keyhole.
• 鍵穴に差し込む
  • に marks the keyhole as the destination into which the key is inserted.
• 鍵穴 and 鍵
  • 鍵穴 is the opening for a key, while 鍵 is the key itself.