Word Study
lightship
CIDE DICTIONARY
lightship, n.
A vessel equipped like a lighthouse, carrying at the masthead a brilliant light, and moored off a shoal or place of dangerous navigation where a permanent lighthouse would be impracticable, to serve as a guide for mariners; as, the Ambrose lightship off New York was rammed and damaged in 1950 by the Santa Monica. [1913 Webster]
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