The term 'coerce forcefully' can be summarized by the word 'DRAGOON, ' which is a seven-letter word. DRAGOON is a military term that refers to the use of force or threats to compel someone to do something. It is derived from the French word 'DRAGON, ' which was used to describe a type of cavalry unit in the 17th century. Dragooning is often used as a form of coercion, especially in military contexts, and it has been used throughout history to achieve political or military objectives.