Fishy bit of protection for men in hose (8)
I believe the answer is:
codpiece
'protection for men in hose' is the definition.
I can't tell whether this definition defines the answer.
'fishy bit' is the wordplay.
'fishy' becomes 'cod' (type of fish).
'bit' becomes 'piece' (synonyms).
'cod'+'piece'='CODPIECE'
'of' is the link.
Can you help me to learn more?
(Other definitions for codpiece that I've seen before include "for promotion of virility?" , "Medieval male accoutrement for the nether regions" , "What kept privates in place" , "Male dress item of former times" , "men put on centuries ago" .)