/siːld ˈɪnstrəmənt/ – Phrase
Definition: Tài liệu được niêm phong.
A more thorough explanation: a contract that has been signed and sealed (=officially stamped or marked). A document that has been sealed may be subject to specific rules, depending on the jurisdiction.
Example: Section 1929 of the Civil Code states “All distinctions between sealed and unsealed instruments are abolished.”