A hollow utensil, such as a cup, vase, or pitcher, used as a container, especially for liquids. Nautical A craft, especially one larger than a rowboat, designed to navigate on water. An airship. Anatomy A duct, canal, or other tube that contains or conveys a body fluid: a blood vessel. Botany One of the tubular conductive structures of xylem, consisting of dead cylindrical cells that are attached end to end and connected by perforations. They are found in nearly all flowering plants. A person seen as the agent or embodiment, as of a quality: a vessel of mercy.