The term 'great weight' can be broken down into five crossword solutions: BULK (4 letters), heftiness (9 letters), ONUS (4 letters), TON (3 letters), and HEFT (4 letters). BULK refers to the mass or volume of something, while heftiness is a synonym for heaviness. ONUS is a burden or responsibility, and a TON is a unit of measurement equal to 2, 000 pounds. HEFT is another word for weight or heaviness. Together, these words all refer to a great amount of weight or heaviness.