What cow does ruins meat, unfortunately (9)
I believe the answer is:
ruminates
'what cow does' is the definition.
'ruins meat unfortunately' is the wordplay.
'unfortunately' indicates an anagram (a bad or unfortunate spelling).
'ruins'+'meat'='ruinsmeat'
'ruinsmeat' anagrammed gives 'RUMINATES'.
(Other definitions for ruminates that I've seen before include "Considers" , "Chews the cud and ponders" .)