splenetic

This term describes a specific kind of irritability characterized by a lingering, caustic bitterness. It suggests a mood that is not just momentarily annoyed, but deeply ingrained and prone to sudden outbursts of spite. It is typically used in formal or literary contexts to describe a personality trait or a prolonged state of hostility. In a medical context, the word refers strictly to the anatomical spleen. This dual usage stems from the ancient belief that the spleen was the seat of melancholy and anger, linking the physical organ to the emotional state of irritability.