·adj Capable of being irriated.
II. Irritable ·adj Susceptible of irritation; unduly sensitive to irritants or stimuli. ·see Irritation, ·noun, 3.
III. Irritable ·adj Very susceptible of anger or passion; easily inflamed or exasperated; as, an irritable temper.
IV. Irritable ·adj Endowed with irritability; susceptible of irritation; capable of being excited to action by the application of certain stimuli.