IPA: /ˈmɑːr.lɪnˌspaɪk/
KK: /ˈmɑr.lɪnˌspaɪk/
A tool used in sailing and rigging, typically made of metal or wood, with a pointed end for separating strands of rope or for splicing.
The sailor used a marlinspike to untangle the ropes on the ship.
Marlinspike is formed from "marlin" (a type of fish, possibly from the Spanish "marlin", a diminutive of "mar" meaning sea) and "spike" (from Old English "spica", meaning a pointed tool or implement). The word refers to a pointed tool used in maritime activities, often associated with the sea and fishing.
Think of the 'mar' in 'marlin' as relating to the sea, and 'spike' as a pointed tool — together, they describe a tool used in sea-related tasks.
No commonly confused words.