The term 'Rigid Airship' is a type of aircraft that was popularized by the German inventor Count Ferdinand von ZEPPELIN in the early 1900s. The term 'ZEPPELIN' is an 8-letter word that is often used to refer to this type of airship. Rigid airships are characterized by their large size, rigid internal structure, and the use of gas cells to provide lift. They were used for both commercial and military purposes during the early 20th century, but have since been largely replaced by other forms of aircraft.