peevish
Easily annoyed and grumpy about small, unimportant things.
Peevish means easily irritated or bad-tempered, especially about small, unimportant things. A peevish person gets cranky over minor annoyances that most people would shrug off: a squeaky door, a wrinkled paper, someone chewing too loudly.
You might feel peevish when you're tired, hungry, or just having a rough day. Everything seems more annoying than it should be. Your shoelace breaks and you snap at your brother. Your pencil rolls off your desk and suddenly the whole world feels frustrating. That grumpy, irritable mood is peevishness.
The word suggests childish irritability rather than serious anger. A peevish complaint sounds like whining: “This sandwich is cut wrong!” or “Why does she always hum that song?” Adults sometimes describe overtired toddlers as peevish when they fuss about everything.
When you notice yourself getting peevish about trivial things, it's often a sign you need rest, food, or a change of scene. A peevish tone of voice makes others less sympathetic to real problems you might have, since constant complaining about small stuff makes people tune you out.