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marlinespike

American  
[mahr-lin-spahyk] / ˈmɑr lɪnˌspaɪk /
Also marlinspike,

noun

Nautical.
  1. a pointed iron implement used in separating the strands of rope in splicing, marling, etc.


marlinespike British  
/ ˈmɑːlɪnˌspaɪk, ˈmɑːlɪŋˌspaɪk /

noun

  1. nautical a pointed metal tool used as a fid, spike, and for various other purposes

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of marlinespike

1620–30; originally marling spike. See marl 2, -ing 1, spike 1