Vindictive

/vɪnˈdɪktɪv/ adjective medium

Driven by a desire for revenge, often over a small or old grievance.

Her vindictive ex kept posting old photos just to embarrass her at work.

Memory Trick

Vindictive shares a root with 'vindicate,' but takes a darker turn -- instead of pursuing justice, a vindictive person pursues personal payback.