Nacelle for a turbofan, said nacelle having: - a fixed structure - a fixed cowl mounted fixedly on the fixed structure and a mobile cowl that is able to move in translation relative to the fixed structure in a direction of translation between an advanced position in which it is moved close to the fixed cowl and a retracted position in which it is moved away from the fixed cowl towards the rear, so as to define between them an opening connecting a duct for a bypass flow and the exterior of the nacelle, - an actuator intended to move the mobile cowl from the advanced position to the retracted position and vice versa - a reverser flap mounted so as to be able to move in rotation about a main axis of rotation on the mobile cowl between a stowed position in which it is positioned outside the bypass duct and a deployed position in which it is moved across the duct, and - a deployment system provided so as to coordinate and defer the movement of the reverser flap from the stowed position to the deployed position with the movement of the mobile cowl from the advanced position to the retracted position and vice versa, said deployment system having: - a first slider as one with the mobile cowl, - guide means intended to guide the first slider in translation parallel to the direction of translation relative to the fixed structure between two stop positions, one corresponding to the advanced position and the other to the retracted position, - a first groove having a first part parallel to the direction of translation and a curved second part, wherein the first groove is as one with the fixed structure, - a second slider mounted so as to be able to move in translation in the first groove, characterized in that the deployment system comprises: - a first connecting rod mounted so as to be able to move in rotation on the first slider about a first axis of rotation and having a first end, wherein the first connecting rod is mounted so as to be able to move in rotation on the second slider between the first slider and the first end about a second axis of rotation, and - a second connecting rod of which a first end is mounted so as to be articulated on the first end of the first connecting rod about a third axis of rotation, and of which a second end is mounted so as to be articulated on the reverser flap about a fourth axis of rotation, and in that the rod of the actuator is mounted so as to be articulated on the first connecting rod, and wherein, when the first slider moves from the stop position corresponding to the advanced position to the stop position corresponding to the retracted position, being guided by the guide means, the second slider moves along the first part of the first groove and, from the moment when the first slider reaches the retracted position, the second slider moves along the second part of the first groove, which, owing to its curved shape, causes a rotational movement of the first connecting rod about the first axis of rotation, and therefore the deployment of the second connecting rod and of the reverser flap, which moves from the stowed position to the deployed position. - a fixed structure - a fixed cowl mounted fixedly on the fixed structure and a mobile cowl that is able to move in translation relative to the fixed structure in a direction of translation between an advanced position in which it is moved close to the fixed cowl and a retracted position in which it is moved away from the fixed cowl towards the rear, so as to define between them an opening connecting a duct for a bypass flow and the exterior of the nacelle, - an actuator intended to move the mobile cowl from the advanced position to the retracted position and vice versa - a reverser flap mounted so as to be able to move in rotation about a main axis of rotation on the mobile cowl between a stowed position in which it is positioned outside the bypass duct and a deployed position in which it is moved across the duct, and - a deployment system provided so as to coordinate and defer the movement of the reverser flap from the stowed position to the deployed position with the movement of the mobile cowl from the advanced position to the retracted position and vice versa, said deployment system having: - a first slider as one with the mobile cowl, - guide means intended to guide the first slider in translation parallel to the direction of translation relative to the fixed structure between two stop positions, one corresponding to the advanced position and the other to the retracted position, - a first groove having a first part parallel to the direction of translation and a curved second part, wherein the first groove is as one with the fixed structure, - a second slider mounted so as to be able to move in translation in the first groove, characterized in that the deployment system comprises: - a first connecting rod mounted so as to be able to move in rotation on the first slider about a first axis of rotation and having a first end, wherein the first connecting rod is mounted so as to be able to move in rotation on the second slider between the first slider and the first end about a second axis of rotation, and - a second connecting rod of which a first end is mounted so as to be articulated on the first end of the first connecting rod about a third axis of rotation, and of which a second end is mounted so as to be articulated on the reverser flap about a fourth axis of rotation, and in that the rod of the actuator is mounted so as to be articulated on the first connecting rod, and