Lock it vs Seal

When to use each in English, with meaning, register, and examples.

Lock it

Top 2,000 (common)

Seal

Top 2,000 (common)C1verb
 Lock itSeal
Pronunciation🇬🇧 //lɒk ɪt//🇺🇸 //lɑk ɪt//🇬🇧 /["/siːl/","/siːlz/","/siːld/","/ˈsiːlɪŋ/"]/🇺🇸 /["/siːl/","/siːlz/","/siːld/","/ˈsiːlɪŋ/"]/
MeaningTo secure something by closing it.A sea animal that has flippers and can swim.
ExampleMake sure to lock it before you leave the house.Please seal the envelope before you mail it to ensure the contents don't fall out.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 2,000 (common)
CEFR level-C1
Part of speechverb
Collocationslock it up, lock it down, lock it securelycarefully, properly, tightly, from, with, carefully, properly, tightly, from, with
Antonyms-open, unseal, uncover
Common mistakesConfuse with 'unlock it', which means to open something., Omitting the object, e.g., saying 'lock' without specifying what is locked.Confused with 'ceal' — make sure to remember the correct spelling., Using 'seal' when they mean 'sign' or 'approval'., Mispronouncing the word, often saying it like 'see-al'.
Usage notesUse 'lock it' when referring to securing doors, cabinets, or devices. Suitable for most contexts. Avoid slang situations.Use 'seal' when referring to the animal or when discussing sealing something in a formal context. Avoid using in informal conversations unless referring to the animal.

See it in real clips

Lock it

Frequently asked questions: Lock it vs Seal

What's the difference between Lock it and Seal?

Lock it: To secure something by closing it. Seal: A sea animal that has flippers and can swim.

Can you show an example of each?

Lock it: Make sure to lock it before you leave the house. Seal: Please seal the envelope before you mail it to ensure the contents don't fall out.

Can I use Lock it and Seal interchangeably?

Not always. Lock it and Seal are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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