Did you know?

Click any word in a definition or example to find the entry for that word

seal - definition and synonyms

What are red words?

90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

Thesaurus diagram

The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.

verb [transitive]     seal pronunciation in American English
Word Forms
present tense
present participlesealing
past tensesealed
past participlesealed
  1. seal


    seal up

    to close a container or space by covering it with something so that air or other substances cannot get in or out
    seal something with something:

    Seal the box with tape.

    Small gaps can be sealed with wax.



to manipulate someone psychologically so that they begin to question their own perceptions and memories

BuzzWord Article

Open Dictionary

Dunning-Kruger effect

the phenomenon by which an incompetent person is too incompetent to understand his own incompetence

add a word


A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today.

global English and language change from our blog
Macmillan learn live love play