One of Henry's Catherines (4)
I believe the answer is:
parr
'one of henry's catherines' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for parr that I've seen before include "Wife who survived" , "Young salmon or trout" , "Young salmon - wife of Henry VIII" , "Catherine --, last wife of Henry VIII" , "Fish" .)