Other forms: unpacked; unpacking; unpacks
To unpack is to take stuff out that's been packed, like the clothing in your suitcase or the fragile item that's been buried in ten thousand Styrofoam peanuts.
If a large shipment arrives at a company, it may take several people to unpack the items and take stock of the contents. We also use unpack to describe analyzing something by taking it apart. This is sort of like unpacking a box or unpacking your luggage, because you're dismantling the components of something, but it's more likely an idea than a physical object.