helepole
noun
hel·e·pole ˈhe-lə-ˌpōl 
variants or less commonly helepolis
hə-ˈle-pə-ləs
plural helepoles ˈhe-lə-ˌpōlz also helepolises hə-ˈle-pə-lə-səz
also helepolises hə-ˈle-pə-lə-səz : an ancient siege engine composed of a movable tower covering a battering ram
Word History
Etymology
French & Latin; French hélépole, from Latin helepolis, from Greek helepolis, from helein to take + polis city