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We have measured the spectrum of liquid hydrogen deuteride in the region of the fundamental band ($3500-4000cm-1$) and of the pure rotational R(0) transition ($80-90cm-1$). The experiments were performed using a Bomem DA3.002 spectrometer and a 1 cm path; the liquid was followed along the gas-liquid coexistence line from 18 to 35 $\mathrm{<mrow\; data-mjx-texclass="ORD">\circ </mrow>}K$. Of special interest are the effects of interference between the permanent dipole moment of HD and the transient dipoles induced during molecular collisions. These effects have been studied in the gas $phase,1$ and were also observed in solid $HD.2$ We observe a pronounced anomalous dispersion (Fano) lineshape for the $R1(0)$ transition around $3715cm-1$, whereas the $R0(0)$ transition around $88cm-1$ is only slightly asymmetric. A weak, sharp absorption feature was observed in the liquid at 18 $\mathrm{<mrow\; data-mjx-texclass="ORD">\circ </mrow>}K$ on the high frequency side of the broader Fano $R1(0)$ profile; this feature resembles the beginning of the stronger sharp feature observed in the $solid.2$