Toothed-shaft system comprising a toothed shaft and a functional element which can be, or is, fastened on the toothed shaft , wherein the toothed shaft has an outer toothing extending parallel to an axis of rotation of the toothed shaft , wherein the functional element has an inner toothing , and wherein the outer toothing of the toothed shaft and the inner toothing of the functional element can be made to engage, or do engage, one inside the other, wherein - one of the interengageable or interengaging toothings (11; 21) has first toothing gaps (11a; 21a*) and second toothing gaps (11b; 21b*), and - the other one of the interengageable or interengaging toothings (21; 11) has interference-fit-toothing teeth (21a; 11a*), wherein a clearance-fit toothing can be, or is, formed by engagement of the interference-fit-toothing teeth (21a; 11a*) in the first toothing gaps (11a; 21a*), and wherein an interference-fit toothing can be, or is, formed by engagement of the interference-fit-toothing teeth (21a; 11a*) in the second toothing gaps (11b; 21b*), and wherein a toothing-free portion is arranged and/or formed adjacent to the first and second toothing gaps (11a, 11b; 21a*, 21b*), characterized in that the first toothing gaps (11a; 21a*) and the second toothing gaps (11b; 21b*) are formed in a common toothing portion (V) of the toothing (11; 21) and are distributed over the circumference of the latter (11; 21), wherein the toothing-free portion is arranged and/or formed adjacent to the common toothing portion (V) of the toothing (11; 21), said common toothing portion being provided with the first and second toothing gaps (11a, 11b; 21a*, 21b*). - one of the interengageable or interengaging toothings (11; 21) has first toothing gaps (11a; 21a*) and second toothing gaps (11b; 21b*), and - the other one of the interengageable or interengaging toothings (21; 11) has interference-fit-toothing teeth (21a; 11a*), wherein a clearance-fit toothing can be, or is, formed by engagement of the interference-fit-toothing teeth (21a; 11a*) in the first toothing gaps (11a; 21a*), and wherein an interference-fit toothing can be, or is, formed by engagement of the interference-fit-toothing teeth (21a; 11a*) in the second toothing gaps (11b; 21b*), and wherein a toothing-free portion is arranged and/or formed adjacent to the first and second toothing gaps (11a, 11b; 21a*, 21b*), characterized in that the first toothing gaps (11a; 21a*) and the second toothing gaps (11b; 21b*) are formed in a common toothing portion (V) of the toothing (11; 21) and are distributed over the circumference of the latter (11; 21), wherein the toothing-free portion is arranged and/or formed adjacent to the common toothing portion (V) of the toothing (11; 21), said common toothing portion being provided with the first and second toothing gaps (11a, 11b; 21a*, 21b*). wherein a clearance-fit toothing can be, or is, formed by engagement of the interference-fit-toothing teeth (21a; 11a*) in the first toothing gaps (11a; 21a*), and wherein an interference-fit toothing can be, or is, formed by engagement of the interference-fit-toothing teeth (21a; 11a*) in the second toothing gaps (11b; 21b*), and wherein a toothing-free portion is arranged and/or formed adjacent to the first and second toothing gaps (11a, 11b; 21a*, 21b*), characterized in that the first toothing gaps (11a; 21a*) and the second toothing gaps (11b; 21b*) are formed in a common toothing portion (V) of the toothing (11; 21) and are distributed over the circumference of the latter (11; 21), wherein the toothing-free portion is arranged and/or formed adjacent to the common toothing portion (V) of the toothing (11; 21), said common toothing portion being provided with the first and second toothing gaps (11a, 11b; 21a*, 21b*). <EOS>