Rope seen in frigate, the rigging (6)
I believe the answer is:
tether
'rope' is the definition.
(thesaurus)
'in frigate the rigging' is the wordplay.
'in' indicates a hidden word.
'TETHER' is hidden within 'frigate the rigging'.
'seen' acts as a link.
(Other definitions for tether that I've seen before include "End of ones --" , "Restrain a horse with a rope" , "Rope for tying animals" , "Rope to hobble grazing animal" , "lead" .)