Nowadays some poetry is hostile (7)
I believe the answer is:
adverse
'hostile' is the definition.
(thesaurus)
'nowadays some poetry' is the wordplay.
'nowadays' becomes 'ad'.
'some poetry' becomes 'verse' ('verse' can be a synonym of 'poetry').
'ad'+'verse'='ADVERSE'
'is' acts as a link.
(Other definitions for adverse that I've seen before include "Detrimental" , "Inopportune" , "'Unfavourable, contrary (7)'" , "Opposed to or unfavourable" , "In an opposing direction" .)