NOZZLE

A nozzle ejecting liquid and nozzle device ejecting a liquid upon mixing an abrasive into a liquid jet stream, obtains a converged jet stream. A nozzle includes: a main body; a buffer chamber in the body, whose central axis is an axis line being the liquid jet stream central line; a constrictor part ejecting the liquid, in a buffer chamber plane on a buffer chamber front side and whose central axis is the axis line; a disk plate inside the buffer chamber, facing the plane on the buffer chamber front side and whose central axis is the axis line; a supporting member supporting the disk plate within the buffer chamber; a supply opening in the body supplying the liquid; and an inflow channel along a direction different from the axis line extending direction, opened on a disk plate rear side and the buffer chamber and communicating with the opening.