ship money

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A tax once levied on English maritime towns and shires to provide ships for war.

Wiktionary

1. n. historical A tax applied to coastal towns for their defence in wartime.

GNU Webster's 1913

1. n. (Eng. Hist.) an imposition formerly charged on the ports, towns, cities, boroughs, and counties, of England, for providing and furnishing certain ships for the king's service. The attempt made by Charles I. to revive and enforce this tax was resisted by John Hampden, and was one of the causes which led to the death of Charles. It was finally abolished.

WordNet 3.0

1. n. an impost levied in England to provide money for ships for national defense