In Celtic mythology, Dis was the Roman name assigned to the supreme god of the Celts by Julius Caesar. Nobody knows which Celtic god this refers to.
In Dante's The Divine Comedy, Dis was both the name of the city separating the fifth and sixth circles of Hell and an alternate name for Lucifer.
In keeping with this general theme, Dis is also the name of the virtual machine within the Inferno computer operating system. Dis was designed to execute programs written in the programming language Limbo.
Dis is also an Ebonics slang word for 'disrespect'.