  We report results on the electrodynamic response of $TiOCl$, a
low-dimensional spin-1/2 quantum magnet that shows a spin gap formation for
T$<T_{c1}$= 67 $K$. The Fano-like shape of a few selected infrared active
phonons suggests an interaction between lattice vibrations and a continuum of
low frequency (spin) excitations. The temperature dependence of the phonon mode
parameters extends over a broad temperature range well above $T_{c1}$,
indicating the presence of an extended fluctuation regime. In the temperature
interval between 200 $K$ and $T_{c1}$ there is a progressive dimensionality
crossover (from two to one), as well as a spectral weight shift from low
towards high frequencies. This allows us to identify a characteristic energy
scale of about 430 $K$, ascribed to a pseudo spin-gap.
