Bookworm has bizarre red ear (6)
I believe the answer is:
reader
'bookworm' is the definition.
(I've seen this in another clue)
'bizarre red ear' is the wordplay.
'bizarre' indicates anagramming the letters.
'red'+'ear'='redear'
'redear' with letters rearranged gives 'READER'.
'has' is the link.
(Other definitions for reader that I've seen before include "University academic" , "Peruser of texts" , "Person addressed by author" , "Peruser, of books perhaps" , "Text book -- red ear (anag)" .)