seamark

• sea mark

From sea +‎ mark. Compare landmark.

seamark (plural seamarks)

1. Any elevated object on land which serves as a guide to mariners, such as a hill or steeple.
2. A beacon, buoy, etc. placed in the sea to aid navigation.
   • c. 1608–1609 (date written), William Shakespeare, “The Tragedy of Coriolanus”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act V, scene iii], line 74:

     Like a great sea-mark, standing every flaw, / And saving those that eye thee!

• Amakers