from The Century Dictionary and Cyclopedia
- n. Any elevated object on land which serves for a direction to mariners in entering a harbor, or in sailing along or approaching a coast; a beacon, as a light-house, a mountain, etc.
Onward they sailed along the south bank of the estuary, past the great sea-carved stone arches of “Île Percée” that made it an important seamark.
The men came back saying they'd set up a seamark, but there was no place for a port.
The ruins of the Cistercian Church which once graced this shore and raised above the trees its lighthouse tower, a seamark by day and a beacon by night, are among the loveliest in Wessex.
The sound of the strokes recalled his mind for the moment to those early days, when the ambition for a seat in Parliament had been the very seamark of his utmost sail.
Where lies your landmark, seamark, or soul's star?
Then falling into a moment’s revery, he again looked up towards the sun and murmured to himself: “Thou seamark! thou high and mighty Pilot! thou tellest me truly where I am — but canst thou cast the least hint where I shall be?
The word 'seamark' comes from 'sea' + 'mark', on the model of 'landmark'.