Palaniammal was a tenant of Ramamurthy, a retired cooperative bank employee, at P N Pudur in the city.
The prosecution case was that Ramamurthy asked Palaniammal to vacate the house following which there was some argument and in a fit of anger, she pushed him on September 26 last year.
Ramamurthy fell down and died on the spot, according to the prosecution.
Special court judge Gunasekharan pronounced the verdict.