To remove from a package or container, particularly with respect to items that had previously been arranged closely and securely in a pack.
They didn't have time to unpack their bags before going out to dinner.
To empty containers that had been packed.
They didn't have time to unpack before going to dinner.
To analyze a concept or a text.
(of a segment such as a vowel) To undergo separation of its features into distinct segments.
To decompress.