The present participle of 'fid'—the act of using a fid tool to manage or separate rope strands in nautical work.
As above with 'fidded'—derived from the noun 'fid' and the Dutch nautical tradition. Adding '-ing' creates the continuous action form.
This word is almost extinct now since modern ships use different rope materials and techniques, making 'fidding' a ghost word that tells us about how maritime technology has transformed.
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