Pettish, a. — Webster enters it under “pettish”
Etymology: [From Pet.]
Fretful; peevish; moody; capricious; inclined to ill temper. "A pettish kind of humor." Sterne. -- Pet"tish*ly, adv. -- Pet"tish*ness, n.
Shades of meaning
Fernald has no entry of its own for pettishness; he lists it under anger.
Where he writes about it:
Impatience, fretfulness, irritation, peevishness, pettishness, petulance, and vexation express the slighter forms of anger. — from anger
Fretfulness, pettishness, and peevishness are chronic states finding in any petty matter an occasion for their exercise. — from anger