  We report the observation of cluster glass-like properties in a double
perovskite ruthenate Ba$_2$CoRuO$_6$ through structural (neutron and
synchrotron X-ray diffraction), magnetic and transport measurements. The system
exhibits classic glassy characteristics like a frequency dependence in ac
Susceptibility, aging and memory effects along with persistance of short-range
correlations upto room temperature. The significant ($\sim30\%$) anti-site
disorder on the dimer sites, coupled with the inherent geometrical frustration,
allows a variety of exchange (both antiferro- and ferromagnetic) interactions
to be distributed randomly across the lattice. On cooling, locally dominant
interactions cause spins to nucleate and form local, short-range ordered
clusters which grow in size until a global freezing occurs at about $T_f \sim
43K$.
