1. A method for aiding in geometric modeling of a first object on the basis of a generic model of the first object and of at least one specific model of at least one second object including at least part of the first object, the method comprising: acquiring the generic model of the first object; acquiring the at least one specific model of the at least one second object; extracting at least one datum for a curve portion from the at least one specific model of the at least one second object according to at least one parameter of the generic model of the first object; determining extrema of the curve portion extracted from the at least one specific model; and adapting the curve portion of the generic model corresponding to the curve portion extracted from the at least one specific model such that the extrema of the curve portion of the generic model are similar to the extrema of the curve portion extracted from the at least one specific model constructing an instantiated model, which is dynamic and modifiable, of the first object on the basis of an adaptation generic model of the first object and of the curve portion extracted from the at least one specific model of the at least one second object.