Find Antonyms
seal Antonyms
Opposite of seal
Because the opposite of seal shifts with each meaning, the 10 antonyms and opposite words below are separated across 3 exact definitions and ranked by contrast strength.
• verb (Context 1)
To close or fasten tightly to prevent anything from passing in or out.
Usage Example
"She carefully sealed the envelope before dropping it into the mail slot."
Strongest
unseal
open
unfasten
Strong
unlock
• verb (Context 2)
To guarantee, secure, or finalize an agreement or decision irrevocably.
Usage Example
"The two executives shook hands to cancel the lucrative business deal."
Strongest
cancel
call off
Strong
break
nullify
void
• verb (Context 3)
To coat a surface with a protective substance to prevent moisture or dirt from penetrating.
Usage Example
"You should strip the wooden deck before winter to protect it from the snow and rain."
Strong
strip
Similar words to seal
Words similar to seal shift depending on context. Common synonyms include:
clinch
signet
waterproof
close
finalize
gasket
fasten
weatherproof
Cite this Entry
Wordmom. (2026). Antonyms for Seal. In Wordmom Thesaurus. Retrieved Nov 5, 2026, from https://wordmom.com/antonyms/seal