Sails may be made from this fibre (5)
I believe the answer is:
sisal
'this fibre' is the definition.
(sisal is a kind of fibre)
'sails may be' is the wordplay.
'may be' indicates anagramming the letters.
'sails' anagrammed gives 'SISAL'.
'made from' is the link.
(Other definitions for sisal that I've seen before include "Ropemaker" , "Fibre-yielding agave" , "Natural fibre" , "Rope-fibre made from leaves of tropical plant" , "Plant yielding rope fibre" .)