Monstrosities seeing English rose upset after word of agreement (8)
I believe the answer is:
eyesores
'monstrosities' is the definition.
'english rose upset after word of agreement' is the wordplay.
'english' becomes 'e' (abbreviation).
'upset' indicates an anagram.
'after' means one lot of letters go next to another.
'word of agreement' becomes 'yes' (I've seen this before).
'rose' is an anagram of 'ores'.
'ores' after 'yes' is 'yesores'.
'e'+'yesores'='EYESORES'
'seeing' is the link.
(Other definitions for eyesores that I've seen before include "They're very ugly to the eye" , "unattractive prospects" , "ugly looking things" , "They are offensive to see" , "views people find offensive" .)