1 [intransitive and transitive]
to take everything out of a box, bag, suitcase etc:
I haven't had a chance to unpack yet.
She unpacked her suitcase and headed for the beach.
Maggie carefully unpacked the gifts she had bought.
to make an idea or problem easier to understand by considering all the parts of it separately:
Some of the issues surrounding mental illness have been unpacked in Chapter 3.