What does "fid" mean?

Fid: A wooden or metal bar or pin, used to support or steady anything.

Additional senses

  1. 2.A pin of hard wood, tapering to a point, used to open the strands of a rope in splicing. Note: There are hand fids and standing fids (which are larger than the others, and stand upon a flat base). An iron implement for this purpose is called a marline spike.
  2. 3.(Mil.) A block of wood used in mounting and dismounting heavy guns.

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