A dosing device comprises a rod element and a shell (4). The rod element has a stem with a longitudinal axis and a first thread arrangement. The shell (4) has a second thread arrangement (411). The first thread arrangement of the rod element or the second thread arrangement (411) of the shell (4) comprises a thread (411). The first thread arrangement of the rod element and the second thread arrangement (411) of the shell (4) engage. The rod element is movable along the longitudinal axis of its stem by rotating the shell (4) and the rod element relative to each other causing the first thread arrangement of the rod element and the second thread arrangement (411) of the shell (4) to travel along each other. A dosage chamber is formed by moving the rod element along the longitudinal axis of its stem. The volume of the dosage chamber is varied by moving the rod element along the longitudinal axis of its stem. An inclination angle (α, β) of the thread (611) varies along the thread (611). The dosing device according to the invention can allow for a precise and convenient dosing of a liquid out of a container. In particular, it can allow for efficiently dosing a comparably small volume out of a comparably large container.L'invention concerne un dispositif de dosage comprenant un élément barre et une enveloppe (4). L'élément barre comporte une tige ayant un axe longitudinal et un premier ensemble filetage. L'enveloppe (4) présente un second ensemble filetage (411). Le premier ensemble filetage de l'élément barre ou le second ensemble filetage (411) de l'enveloppe (4) comprend un filetage (411). Le premier ensemble filetage de l'élément barre et le second ensemble filetage (411) de l'enveloppe (4) viennent en prise. L'élément barre est mobile le long de l'axe longitudinal de sa tige par rotation de l'enveloppe (4) et de l'élément barre l'un par rapport à l'autre amenant le premier ensemble filetage de l'élément barre et le second ensemble filetage (411) de l'enveloppe (4) à s
