1) Angry 2) Bristly 3) Cross 4) Edgy 5) Hotheaded 6) Iracund 7) Irate 8) Ireful 9) Irous 10) Irritable 11) Ornery 12) Quick tempered 13) Splenetic 14) Surly 15) Testy 1) Cantankerous 2) Characterized by anger 3) Choleric 4) Easily angered 5) Easily provoked to anger 6) French word used in English 7) Hot-tempered 8) Hotheaded 9) Ill-natured 10) Irritable easily angered 11) Petulant 12) Quick-tempered 13) Quickly aroused to anger 14) Short 15) Short-tempered 16) Testy 
• (a.) Prone to anger; easily provoked or inflamed to anger; choleric; irritable; as, an irascible man; an irascible temper or mood.
I·ras'ci·ble adjective [ Latin irascibilis , from irasci to be angry, ira anger: confer French irascible . See Ire .] Prone to anger; easily provoked or inflamed to anger; choleric; irritable; as, an irascible man; an irascible temper or mood. -- 
irritable easily angered 
irascible 1. Easily provoked to anger or outbursts of temper. 2. Very irritable; such as, an irascible old man. 2. Characterized or produced by anger; such as, an irascible response.
easily provoked to anger; very irritable: an irascible old man. · characterized or produced by anger: an irascible response.
quickly aroused to anger