In this paper, we propose and experimentally demonstrate a temporal ghost imaging scheme which generates a magnified ghost image of an ultrafast waveform. Inspired by shadow imaging in the spatial domain and building on the dispersive Fourier transform of an incoherent supercontinuum in an optical fibre, the approach overcomes the resolution limit of standard time-domain ghost imaging generally imposed by the detectors speed. See http://aip.scitation.org/doi/full/10.1063/1.4977534