礼

1. Origins, structure, and basic meaning

• Structure: 礼(れい) means a courteous greeting or an expression of gratitude.
• Basic usage: It appears in greetings before and after a match and in thanks for help received.

2. Common pitfalls and similar expressions

• The act of greeting respectfully
  • 礼をする describes making a respectful greeting, such as bowing.
• に marking something done in thanks
  • 助けてもらった礼に means as a gesture of thanks for having received help.