English Dictionary

unseal

/ʌnˈsiːl/

verb

(transitive) To break the seal of (something) in order to open it. / (intransitive) To open by having a seal broken.

He carefully unseals the envelope.

意味（1）

(transitive) To break the seal of (something) in order to open it.

意味（2）

(intransitive) To open by having a seal broken.

But it's just the equalising of pressure as the vault door unseals.