Roy set out assortment of seafood (6)
I believe the answer is:
oyster
'assortment of seafood' is the definition.
'oyster' can be an answer for 'seafood' (oyster is a kind of seafood). I'm unsure of the 'assortment of' bit.
'roy set out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'roy'+'set'='royset'
'royset' anagrammed gives 'OYSTER'.
Can you help me to learn more?
(Other definitions for oyster that I've seen before include "Content of stew" , "Source of natural pearls" , "Marine bivalve" , "Pearl-generating bivalve" , "Mollusc with shucks" .)