  The spin, charge, and lattice degrees of freedom and their interplay in high
entropy oxides were intensively investigated in recent years. However, how the
orbital degree of freedom is affected by the extreme disorder in high entropy
oxides hasn't been studied. In this work, using perovskite structured
\textit{R}VO$_3$ as a materials playground, we report how the disorder arising
from mixing different rare earth ions at the rare earth site affects the
orbital ordering of V$^{3+}$ t$_{2g}$-electrons. Since each member of
\textit{R}VO$_3$ crystallizes into the same orthorhombic \textit{Pbnm}
structure, the configurational entropy should not be critical for the success
synthesis of (\textit{R}$_1$,...,\textit{R}$_n$)VO$_3$. The spin and orbital
ordering was studied by measuring magnetic properties and specific heat of
single crystals. Rather than the number and type of rare earth ions, the
average ionic radius and size variance are the key factors determining the spin
and orbital order in (\textit{R}$_1$,...,\textit{R}$_n$)VO$_3$. When the size
variance is small, the average ionic radius takes precedence in dictating spin
and orbital order. Increasing size variance suppresses the G-type orbital order
and C-type magnetic order but favors the C-OO/G-AF state and the spin-orbital
entanglement. These findings suggest that the extreme disorder introduced by
mixing multiple rare earth ions in high entropy perovskites might be employed
to preserve the orbital degree of freedom to near the magnetic ordering
temperature, which is necessary for the electronic driven orbital ordering in a
Kugel-Khomskii compound.
