A nipple for spokes of spoked wheels includes a rod with an axial development, a threaded hole which is formed axially in the rod, the thread of the hole defining a root diameter and a crest diameter, a head which is widened with respect to the rod and a deformable insert which is inserted in a seat which is axially aligned with the hole and which is constructed in an axially intermediate position thereof. The insert, at least when it is inserted in the seat, has a passage for a threaded spoke end, the internal diameter of which is less than the root diameter of the thread of the hole so as to interfere with the thread of the spoke when it is screwed into the threaded hole.