Other forms: unpacking, unpacked, unpacks
To unpack is to take things out of a case or a box. Unpack the suitcase, still unpacking, unpack the shopping.
The un- here reverses the action, as it does in undo and unlock. There is a very common figurative sense in academic and journalistic writing: to unpack an argument is to separate out what is inside it — let us unpack that. It irritates some readers and is genuinely useful. In computing, to unpack an archive is to extract the files. Note unpacked, and that boxes stay unpacked for years.
1verbunpackTo take things out of a case or box.
“As soon as we got to the hotel, we unpacked our suitcases.”
2verbseparateTo separate out what is inside an argument.
“The teacher helped us unpack the poem's meaning line by line.”
unpack is a taking out.
The verb is un- plus pack, and pack came from Dutch or Low German trading language along with most of the vocabulary of warehouses. The reversing un- is native English and attaches to anything.
Middle English
unpakken
English, today
unpack
From Middle English unpakken, equivalent to un- + pack. Compare stq uutpakje (“to unpack”), West Frisian útpakke (“to unpack”), Dutch uitpakken (“to unpack”), German auspacken (“to unpack”).
Etymology from Wiktionary, CC BY-SA