lightship

/ˈlaɪtˌʃɪp/
noun
  1. A ship that stays in one place at sea and uses a bright light to warn other ships of danger or to guide them, especially near a harbor or dangerous area.
    • The old lightship was anchored near the rocky coast to warn sailors of the shallow waters.
    • Before modern GPS, a lightship was essential for safe navigation in foggy weather.
    • Tourists can visit the historic lightship docked at the maritime museum.
Synonyms
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