petulant (adj) - impatient, irritable, or cranky, often in a childish way; peevish or touchy [pech-uh-luhnt]
BREAKDOWN: PET- (seek) + -UL (relating to) + -ANT (state of)
petulance is the state of childish bad temper or irritable, sulky behavior (also petulancy)
pettish means showing anger and impatience, especially over minor irritations
“If you study a great work of art, you'll probably find the artist was a kind of genius. And geniuses are different to you and me. So let's have no talk of temperamental, self-absorbed and petulant babies. Being a good artist is the toughest job you could pick, and you have to be a little nuts to take it on. I love them all.” —Charles Saatchi