He had an answer ready for everything Lehrer and Obama threw at him, and his answers were punchy and memorable.
"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.