The term 'PACK CARGO' refers to the process of loading and securing cargo onto a ship or other form of transportation. The two crossword solutions, STOW (4 letters) and LADE (4 letters), are both verbs that describe this process. STOW means to arrange and store goods in a particular place, while LADE means to load or fill with goods. Together, these two words describe the process of packing cargo for transport.