The term 'HEAVY BLOW' can be described by a variety of words, including THWACK (6 letters), THUMP (5 letters), THUD (4 letters), SWAT (4 letters), GALE (4 letters), GUST (4 letters), ONER (4 letters), and SLUG (4 letters). THWACK is a sharp sound made when something is struck with force, while THUMP is a dull sound made when something is hit with a heavy object. THUD is a dull sound made when something is dropped or thrown with force. SWAT is a quick, sharp blow, while GALE is a strong wind. GUST is a sudden, brief burst of wind, and ONER is a single, powerful strike. Finally, SLUG is a heavy, slow-moving object.