**Jack at bow** describes the practice of flying a jack from a small staff at the bow of a warship when at anchor or alongside, in addition to the ensign at the stern. The jack is hauled down when the vessel proceeds to sea. The arrangement enables a vessel’s nationality to be seen from any quarter while in port. National regulations specify which jack is flown and on what occasions.
**Example**: A United States Navy warship at anchor flies the Union Jack at the bow and the national ensign at the stern from colours to sunset.
**See also**: [jack](/glossary/jack/), [ensign-at-sea](/glossary/ensign-at-sea/), [ensign](/glossary/ensign/), [hoisting](/glossary/hoisting/)