A broadside's the side of a ship; the battery of cannon on one side of a warship; or their simultaneous (or near simultaneous) fire in naval warfare. In the Age of Sail Broadsides were quite different during older naval warfare, in the Age of Sail. Ships of this era had long rows of guns along each side of the ship: firing all the guns on one side of the ship was a broadside; firing all the guns on both sides was a double broadside. An 18th century man of war like HMS Victory had cannons that w… (More on Broadside)