Definition
A grump is a person who is bad-tempered, irritable, and generally in a sour mood. They aren't necessarily mean, but their negativity can be contagious. Think of a milder version of a grouch, someone who's more passively annoyed than actively complaining. It's often temporary; a grump might just be having a bad day. Unlike someone who's simply sad, a grump expresses their unhappiness through snippy remarks and a general air of discontent. They might scowl a lot or give short answers.