Roy set out to find seafood (6)
I believe the answer is:
oyster
'seafood' is the definition.
(I know that Oyster is a type of seafood)
'roy set out' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'roy'+'set'='royset'
'royset' anagrammed gives 'OYSTER'.
'to find' is the link.
(Other definitions for oyster that I've seen before include "Edible bivalve mollusc" , "Edible marine mollusc" , "It produces pearls" , "Succulent bivalve, may bear a pearl" , "Marine bivalve" .)