Abstract: The diffuser (1) includes a receptacle which contains the odorous substance to be diffused in liquid form or the like, and which is closed by a diffusion membrane (3c), and means for rotating the receptacle about itself. The receptacle includes a plurality of compartments which enable the weight of the odorous substance to be distributed over the periphery of the axis of rotation (DD) of the receptacle. In a preferred embodiment, the receptacle includes at least one annular-type housing (3) which is centered on the axis of rotation of the receptacle, and which is partitioned into a plurality of identical compartments (5a, 5b, 5c, 5d, 5e, 5f).