Punchiness is the quality of writing or speech that is short, clear, and hits the reader or listener hard — not long, not soft, not full of extra words. A punchy sentence does a lot of work in a small space; punchiness is that hit. People use it about slogans, headlines, speeches, and ads more than about long essays. It belongs in a writing class or an office; it is not a stiff legal word. It does not mean how hard someone can hit with a fist, even though punch sounds like that.