Gunboat/ˈɡʌnbəʊt/ Definition 1 of 2Pro Tip 1/3Naval Context Commonly used to refer to naval operations or military presence on water. The coast was patrolled by a fleet of gunboats. Pro Tip 2/3Smaller Vessel Generally smaller than other warships but heavily armed for its size. Despite its size, the gunboat was bristling with firepower. Pro Tip 3/3Quick Deployment Used for rapid deployment where bigger naval ships cannot operate. A shallow river necessitated the use of gunboats.