The word for today is…
irascible (adj) – Easily provoked, testy, touchy, short-tempered.
Source : The Free Dictionary
Etymology : If you try to take apart irascible in the same manner as irrational, irresistible, or irresponsible, you might find yourself wondering what ascible means—but that’s not how irascible came to be. The key to the meaning of irascible isn’t the negative prefix ir- (which is a variant of the prefix in- that is used before words beginning with “r”), but the Latin noun ira, meaning “anger.” From ira, which is also the root of irate and ire, came the Latin verb irasci (“to become angry”) and the related adjective irascibilis, the latter of which led to the French irascible. English speakers borrowed the word from French in the 16th century.
