noun
invitation letter (for visa)
A formal document explaining the reason for inviting a foreign national to Japan, typically required for visa applications.
ビザ申請には招聘理由書の提出が必要です。
Submission of an invitation letter is required for the visa application.
Compound of 招聘 (しょうへい, invitation) + 理由 (りゆう, reason) + 書 (しょ, document).