seal something off
SEAL
noun[ C ]
(alsoSeal)uk /siːl/ us /siːl/
in the US and some other countries, a member of an elite (= especially good and highly trained) force within the navy that deals with special operations that involve water. SEAL is an abbreviation for Sea, Air, and Land Team: （美国或其他国家的）海军三栖特种部队，海豹突击队（Sea, Air, and Land Team 的缩写）
The 23-year-old from Massachusetts wants to become a Navy SEAL.这位来自马萨诸塞州的23岁少年想成为一名海豹突击队队员。
Tributes were paid to the Thai Navy Seal who died during the cave rescue.向在洞穴救援中牺牲的泰国海豹突击队队员致敬。
Captain Shepherd was a former astronaut and a former Seal.
He was a former Navy SEAL commander who headed the Naval Special Warfare Task Unit in the Pacific.
I'm not a tough guy, I'm not a commando, I'm not strong, I'm not intensely trained, I'm not a SWAT guy, I'm not a Navy Seal.
The company was run mainly by former SEALs, men highly trained in military operations.

SMART Vocabulary: related words and phrases

The Navy
admiralty
aircraft carrier
armada
battleship
broadside
cruiser
destroyer
gunboat
HMS
minesweeper
naval
pocket battleship
RFA
RN
seaborne
the Navy Seals
the USN
transport ship
troopship
U-boat

You can also find related words, phrases, and synonyms in the topics:

Parts of armies & groups of servicemen

seal | American Dictionary

seal
noun[ C ]
us/sil/

sealnoun[C] (ANIMAL)

a large, fish-eating mammal that has very thick fur and lives in the sea:
Seals are sometimes hunted for their valuable fur.

sealnoun[C] (OFFICIAL MARK)

an official mark on a document which shows that it is legal or actually what it claims to be:
Diplomas are stamped with the state seal.
A seal of approval means that something has been proven to be good or is very pleasing:
My brother’s girlfriend got my mom’s seal of approval.

sealnoun[C] (COVERING)

anything that prevents the escape of liquid or gas from a container or pipe:
The oil seal broke, and all the oil leaked from the engine.
Don’t use that jar of baby food if the seal is broken.
seal
verb[ T ]
us/sil/

sealverb[T] (CLOSE)

to close a container or opening, or to prevent the escape of a liquid or gas from something:
Rubber seals jars tightly.
He sealed the envelope and put a stamp on it.
[ M ]Broiling with high heat seals in the flavor of the meat.
[ M ]The police sealed off the area (= prevented people from entering it).
If official documents are sealed, they cannot be seen or are not available to the public.

sealverb[T] (APPROVE)

to formally approve an agreement:
They sealed the agreement with their signatures.

seal | Business English

seal
noun[ C ]
uk /siːl/us
an official mark on a document, sometimes made with wax, that shows that it is legal or has been officially approved:
The documents were marked with the official seal.
a thin piece of paper or plastic that covers the opening of a container and has to be broken before the contents can be used:
The seal on the bottle was broken.
something fixed around the edge of an opening to prevent liquid or gas flowing through it:
A video showed cracked seals and leaking water inside the coal mine.
 under seal
LAW
if something is under seal, it cannot be seen, copied, or taken away:
His file is currently under seal.

See also