Part of ship storing bit of rotten rubbish (5)
I believe the answer is:
dreck
'rotten rubbish' is the definition.
'dreck' can be an answer for 'rubbish' (I've seen this before). I'm unsure of the 'rotten' bit.
'part of ship storing bit' is the wordplay.
'part of ship' becomes 'deck' ('deck' is part of 'ship').
'storing' indicates putting letters inside.
'bit' becomes 'r' (I can't justify this - if you can you should believe this answer much more).
'deck' enclosing 'r' is 'DRECK'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for dreck that I've seen before include "Refuse" , "Rubbish" .)