The term 'PACKS TIGHTLY' can be summarized by two crossword solutions: CRAMS (5 letters) and WADS (4 letters). CRAMS is a verb meaning to press or cram something into a small space, while WADS is a noun referring to a small mass of soft material, such as paper or cloth, that has been compressed into a lump. Both words imply the idea of packing something tightly, making them suitable solutions for the term.