歯

1. Origins, structure, and basic meaning

• Structure: 歯（は） means a tooth used for chewing food.
• Basic usage: Use it for brushing after meals or a tooth being damaged by biting something hard.

2. Common pitfalls and similar expressions

• Verbs used with teeth
  • 歯を磨く means brushing one's teeth.
  • 歯が欠ける means that part of a tooth chips off.