Type of knot (7)
'type of knot' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for reef that I've seen before include "Ridge of rock or sand just below sea surface" , "Free (anag.)" , "portion of sail" , "Underwater ridge or kind of knot" , "Coral structure" .)
'type of knot' is the definition.
This is the entire clue.
(Another definition for bowline that I've seen is " Rope".)