The invention concerns a turbofan (1) having a dilution rate of at least 10 and comprising: a fan (2) having a disc (20) provided with blades (22) at the periphery thereof, a distance (H) between the head (22a) of the blades (22) and the housing (24) of the fan being less than or equal to ten millimeters; a primary flow space and secondary flow space that are concentric; a turbine (6), housed in the primary flow space and in fluid communication with the fan (2); and a reduction mechanism (10) coupling the turbine (6) and the fan (2).