The continuous point symmetries of (2 + 1) discrete Volterra system is deri
ved and it forms a centreless infinite-dimensional Kac-Moody Virasoro algeb
ra. Using the symmetries, a similarity reduction of the (2 + 1) Volterra sy
stem to a partial differential-difference equation with two independent var
iables is obtained. Also, the Lie point symmetries of the reduced partial d
ifferential-difference equation is derived and its similarity reduction to
an ordinary differential-difference equation is obtained. The ordinary diff
erential-difference equation reduces to the third Painleve equation in the
continuum limit. Further, a Lax pair for the reduced equation is derived in
dicating its complete integrability.