irritable

Easily irritated or annoyed.

Abnormally or excessively sensitive to a stimulus.

Capable of responding to a stimulus. Used of an organism.

Susceptible to mental irritation; liable to the excitement of anger or passion; irascible; petulant.

Susceptible to physical irritation; capable of being stimulated to action by external agency; liable to contract, shrink, become inflamed, etc., when excited or stimulated.