The name of the Latin-script letter S .
"The biologist concluded that cooperation was an ess for the species, as it ensured survival even when some individuals acted selfishly."
evolutionarily stable strategy
To move in a changing direction, forming the shape of a letter S.
"The snake moved through the tall grass by slithering and essing its way toward the cool water hole."
Initialism of Enterprise Storage Server.
"After configuring our new storage infrastructure, we decided to deploy an ESS to handle the heavy data loads from our video editing department."