指

1. Origins, structure, and basic meaning

• Structure: 指, read ゆび, refers to a finger or toe.
• Basic usage: It is used when being careful with fingers around a knife or describing fingertips numbed by cold wind.
  • 包丁で指を切らないように気をつけて。

2. Common pitfalls and similar expressions

• Finger and toe
  • 指 refers to a finger in the source examples, but 足の指 means a toe. English distinguishes these as finger and toe.