hoop iron

noun
1.
iron in the form of thin strips for bonding masonry, holding barrels together, etc.
Origin
1810-20
Examples from the web for hoop iron
  • Refiners had to pay high prices for barrels because hoop iron was high.
  • Philly armed him self with a heavy piece of hoop iron, and the two boys entered the vault, the youngest one carrying a lantern.