noun
registration certificate; registration card
An official document or card proving that something or someone is registered. Common in administrative and legal contexts.
新しい住所の登録証を市役所で受け取った。
I received my new address registration certificate at the city hall.
この登録証がないと、施設を利用できません。
You cannot use the facility without this registration card.
証明書 is a general certificate or proof document, whereas 登録証 specifically certifies registration.
Compound of 登録 (registration) + 証 (certificate, proof).