Definition:Set Difference/Also known as

Set Difference: Also known as
Some sources refer to $S \setminus T$ as the difference set (as opposed to set difference).

Some authors call $S \setminus T$ the relative difference between $S$ and $T$.

Some authors call $S \setminus T$ the (relative) complement of $T$ in $S$, but the standard definition for the latter concept requires that $T \subseteq S$.

$S \setminus T$ can be voiced:
 * $S$ slash $T$
 * $S$ cut down by $T$.

Another frequently seen notation for $S \setminus T$ is $S - T$.

Both notations may be encountered on this website, but $\setminus$ is preferred.

Some sources use $S \sim T$.