The word "pak" is a colloquial term that is commonly used as a shortened version of "pack." It can refer to putting things into a container or assembling items together for a specific purpose.
We decided to pack them in Tetra Pak ® cartons for several good reasons: (carupetfood.com)
Join Tetra Pak ® at Food Processing Expo 2018 and experience Tetra Recart ®, the retort able carton package that's shaking up the canned food aisle. (tetrapak.com)
Then we visit a temple in Pak Chong with a stern guide who explains everything, doesn't suffer arguments, and wants our full attention. (off-the-beaten-track.net)