Abstract: A single-jet liquid meter comprises a body in which a measurement chamber of substantially cylindrical shape is disposed. The chamber is fitted with a spinner having a longitudinal axis XX' and provided with blades, a liquid feed tube and a liquid discharge tube connected to the body and in alignment on an axis YY' that intersects axis XX' perpendicularly. A housing is disposed in the body around the periphery of the spinner and includes at least two slots respectively facing the feed tube and the discharge tube. The slots are designed to inject and eject the liquid flow in an inclined manner relative to the alignment axis of the tubes. At least one slot faces the feed tube and presents, to the flow of liquid coming from said tube, a shaped surface that progressively increases the speed of the flow.