"nervously anxious; irritable from fatigue," 1937, from punch (v.) + -y (2). Perhaps originally a shortening of punch-drunk. Related: Punchily; punchiness.
"full of vigor," 1926, from punch (n.3) + -y (2). Related: Punchily; punchiness.
Slang definitions & phrases for punchy
punchy
adjective
Exhibiting brain damage from repeated blows to the head; punch-drunk: Sailor Bob, a punchy stumble-bum(1937+)
Feeling somewhat confused and battered, as if punch-drunk: Even if she's a little punchy and hyper from doing a dozen interviews that day(1940s+)
Having force, impact, energy, etc; potent; jazzy, zingy: The English language may someday be as colorful and punchy as it was in Elizabethan times(1926+)