General adjectives:
* Abusive (most common and direct)
* Harmful
* Destructive
* Degrading
* Violent
* Cruel
* Oppressive
* Tyrannical
* Malicious
Adjectives for specific types of abuse:
* Physical abuse: bruising, battering, violent, brutal
* Emotional abuse: manipulative, controlling, toxic, undermining
* Verbal abuse: insulting, demeaning, belittling, degrading
* Sexual abuse: exploitative, predatory, violating, coercive
* Financial abuse: exploiting, controlling, manipulative
* Neglect: inattentive, indifferent, irresponsible, negligent
More nuanced adjectives:
* Systematic (for abuse that is ongoing and organized)
* Intentional (for abuse that is deliberately done)
* Unjustified (for abuse that is without cause)
* Recurring (for abuse that happens repeatedly)
* Patterned (for abuse that follows a specific pattern)
Ultimately, the best adjective to use will depend on the specific situation and the message you want to convey.