Translation guide
The act of closing or fastening something securely, often to prevent opening, leakage, or tampering. This guide covers common Japanese expressions for sealing containers, envelopes, joints, and surfaces.
To seal an envelope, box, or container by closing it with adhesive, tape, or a sticker.
General phrase meaning 'to seal' or 'to close with a seal'. Commonly used for envelopes and containers.
封筒に封をしてください。
Please seal the envelope.
Means 'to close' or 'to shut'. Used for envelopes, books, etc., but does not necessarily imply a seal.
封筒を閉じてください。
Please close the envelope.
Loanword from English 'seal', often used for sealing with stickers or tape.
箱をテープでシールした。
I sealed the box with tape.
To seal a container, joint, or surface to prevent air, water, or other substances from passing through.
Specifically means 'to seal tightly' or 'to make airtight/watertight'. Used for food containers, packages, etc.
食品を密封して保存する。
Store food in an airtight container.
Similar to 密封する, meaning 'to seal tightly' or 'to close hermetically'. Often used in technical contexts.
容器を密閉してください。
Please seal the container tightly.
Means 'to pack' or 'to seal with packing material'. Used for plumbing or mechanical seals.
パイプの継ぎ目をパッキングする。
Seal the pipe joint with packing.
To affix a seal, stamp, or sticker as a mark of authenticity, approval, or closure.
Means 'to seal' with a formal seal or stamp, often for legal or official documents. Implies a mark that must be broken to open.
書類に封印をした。
I put a seal on the document.
Specifically means 'to affix a seal' or 'to stamp'. Used for personal or company seals (hanko).
契約書に捺印してください。
Please affix your seal to the contract.
Refers to using sealing wax, often for decorative or traditional purposes.
手紙にシーリングワックスを使った。
I used sealing wax on the letter.
To block or close off an area, entrance, or passage so that it cannot be used or entered.
Means 'to blockade' or 'to seal off'. Used for roads, areas, or buildings by authorities.
警察が道路を封鎖した。
The police sealed off the road.
Means 'to close' or 'to shut down'. Used for facilities, entrances, or services.
建物の入口を閉鎖した。
They sealed off the entrance to the building.
To finalize or confirm an agreement, often with a handshake or formal act.
Means 'to conclude a contract' or 'to seal a deal'. The most natural way to express finalizing an agreement.
両社は契約を結んだ。
The two companies sealed the deal.
Means 'to reach an agreement'. Less formal than 契約を結ぶ, but still implies finalization.
交渉の末、合意に達した。
After negotiations, they sealed the agreement.
Literally 'to decide with a handshake'. Used for informal agreements, similar to 'seal with a handshake'.
握手で取引を決めた。
We sealed the deal with a handshake.
Both mean 'to seal tightly', but 密封する is more common for everyday items like food containers, while 密閉する is often used in technical or industrial contexts (e.g., hermetically sealed).
この容器は密閉性が高い。
This container has a high sealing property.
シールする is a casual loanword for sticking or taping. For official seals or stamps, use 封印する or 捺印する.
書類にシールするのは不適切です。
It's inappropriate to 'seal' a document with a sticker.