Like many things in medicine the answer is yes and no! For example, a cough can be a symptom of an allergy, a symptom of pneumonia or a symptom of lung cancer... Anger itself is not a mental disease....a cough is not on its own a symptom of pulmonary disease however repetitive episodes of serious anger can be a sign of anything from an autism spectrum disorder to bi-polar disorder or a personality disorder such as borderline personality. Context is everything in life, in medicine and in psychiatry.

Anger is a behavioral problem that can be a symptom of a psychiatric disorder.

Check this out.
https://www.healthyplace.com/other-info/mental-health-newsletter/mental-illness-and-anger