JARGON, n. 1. A word that works perfectly until it doesn't. 2. The moment a specialist discovers, mid-sentence, that they have been living alone inside their own language. 3. What a face looks like when it refuses to pretend. 4. Evidence that expertise is also a kind of enclosure. 5. The gap between the hand's gesture and the meaning it was reaching for. 6. A small hilarious mercy.