Irritable

Part of speech: adjective (a.)

1. Capable of being irriated.

2. Very susceptible of anger or passion; easily inflamed or exasperated; as, an irritable temper. Vicious, old, and irritable. Tennyson.

3. Endowed with irritability; susceptible of irritation; capable of being excited to action by the application of certain stimuli.

4. Susceptible of irritation; unduly sensitive to irritants or stimuli. See Irritation, n., 3.

Synonyms: Excitable; irascible; touchy; fretful; peevish.