The coupling device for a timepiece (400) includes a first part (41;41′;41″), a second part (42;42′;42″) mobile relative to the first part about a first axis (A1;A1′;A1″), at least one blocking element (43;43′;43″), and a control element (45;45′;45″) movably mounted on one of the parts to move between a deactivation first configuration (C1) and an activation second configuration (C2), the device being unidirectional or a freewheel in its activation second configuration (C2), the at least one blocking element (43;43′;43″), the first part (41;41′;41″), and the second part (42;42′;42″) being configured and/or adapted so as to connect the first and second parts by obstacle or by wedging, the at least one blocking element (43;43′;43″) being adapted and/or configured so that, in the first configuration (C1) it enables free relative movement of the first and second parts during rotation in a first direction and in a second direction opposite the first direction, and in the second configuration (C2) it enables coupling of the first and second parts during loading of one or the other in the first direction and free relative movement between the parts during rotation in the second direction.