Eroding badly, being neglected (7)
I believe the answer is:
ignored
'being neglected' is the definition.
(synonyms)
'eroding badly' is the wordplay.
'badly' indicates an anagram (letters in the wrong order).
'eroding' is an anagram of 'IGNORED'.
(Other definitions for ignored that I've seen before include "Paid no attention to" , "cast aside" , "Turned a blind eye to" , "Shunned" , "Disregarded intentionally; failed to consider" .)