Heavy artillery mounted on wheels (6)
I believe the answer is:
cannon
(Other definitions for cannon that I've seen before include "Big gun" , "shot playing billiards" , "Howitzer" , "Great gun" , "Weapon firing large balls" .)
I believe the answer is:
cannon
(Other definitions for cannon that I've seen before include "Big gun" , "shot playing billiards" , "Howitzer" , "Great gun" , "Weapon firing large balls" .)