An intaglio printmaking technique that creates tonal areas. Its name reflects its watercolor-like effects. Powdered resin is sprinkled on a metal plate and adheres through heating. When the plate is submerged in acid, tiny areas unprotected by the resin are “bitten” by the acid, creating recesses. After the resin coating is removed, the plate is inked to fill in these recesses. When damp paper is laid on the plate and run through a press, the tiny ink-filled recesses print as tonal fields.