How to say "signing" in Japanese

• サイン会サインかいCommon
  nounCovers 'signing' as an event: an autograph session where a celebrity, athlete, or author signs autographs for fans, as in a book signing. It is not about signing documents.
• 調印ちょういんJLPT N1approx.Common
  noun, suru verb, intransitive verbThe formal signing of a document — a treaty, agreement, or contract — by the parties concerned, often at a ceremony. This is the word for official and diplomatic signings, not autographs.
  その条件じょうけんは日本にっぽん、ドイツ、イギリス、アメリカの間あいだで調印ちょういんされた。↗

  Terms were signed between Japan, Germany, Great Britain and the United States.
• 加入かにゅうJLPT N1approx.Common
  noun, suru verb, intransitive verbMatches 'signing' only in the sense of signing up: joining a club or organization, or becoming party to a treaty. It denotes the joining itself, not the physical act of signing.
  まさかの時ときのために彼かれは保険ほけんに加入かにゅうした。↗

  He insured himself for a rainy day.

Use 「サイン会」 for a signing as an event where autographs are given, 調印 for the formal signing of documents such as treaties or contracts, and 加入 when 'signing' means joining or becoming a member.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• サイン会サインかいsigning
• 調印ちょういんsignature
• 加入かにゅうjoining (a club, organization, etc.)
• 指話法しわほうfinger language