A keelboat is a riverine cargo-capable working boat, or a small- to mid-sized recreational sailing yacht. The boats in the first category have shallow structural keels, and are nearly flat-bottomed and often used leeboards if forced in open water, while modern recreational keelboats have prominent fixed fin keels, and considerable draft. The two terms may draw from cognate words with different final meaning.

A riverboat is a watercraft designed for inland navigation on lakes, rivers, and artificial waterways. They are generally equipped and outfitted as work boats in one of the carrying trades, for freight or people transport, including luxury units constructed for entertainment enterprises, such as lake or harbour tour boats. As larger water craft, virtually all riverboats are especially designed and constructed, or alternatively, constructed with special-purpose features that optimize them as riverine or lake service craft, for instance, dredgers, survey boats, fisheries management craft, fireboats and law enforcement patrol craft.