General synonyms:
* Ignore
* Disregard
* Overlook
* Dismiss
* Skip
* Pass over
* Slight
* Forgo
* Abandon
* Leave undone
Synonyms emphasizing lack of care:
* Mismanage
* Misuse
* Abuse
* Deprive
* Starve
* Maltreat
* Despise
Synonyms emphasizing lack of attention:
* Forget
* Overlook
* Miss
* Disregard
* Be inattentive to
* Fail to notice
Synonyms emphasizing deliberate inaction:
* Refuse
* Reject
* Shun
* Avoid
* Turn a blind eye to
More specific synonyms:
* Inattention: This emphasizes a lack of focus or care.
* Dereliction: This implies a serious failure to fulfill a duty or responsibility.
* Apathy: This suggests a lack of interest or concern.
* Indifference: This emphasizes a lack of feeling or emotion.
The best synonym to use will depend on the specific situation and the message you want to convey.