The Hebrew word cherem designates something or someone 'devoted' to God — either for sacred service (like a temple gift) or for complete destruction. The 'ban of destruction' (cherem) in holy war meant total annihilation without exception.
Cherem is one of the most theologically charged and uncomfortable words in the Old Testament. When God declared cities 'herem' (Jericho in Joshua 6), it meant total consecration to divine judgment — nothing could be spared for personal gain. Achan's sin (Joshua 7) lay in taking cherem items, treating sacred destruction as personal treasure. This radical concept communicates that sin has no half-measures in God's economy — it must be utterly dealt with. The New Testament fulfillment is the cross, where Jesus became 'a curse' (anathema, the Greek equivalent of cherem) for us (Galatians 3:13).