Verbatim[expr] represents expr in pattern matching, requiring that expr be matched exactly as it appears, with no substitutions for blanks or other transformations.
Verbatim[x_] will match only the actual expression x_.
Verbatim is useful in setting up rules for transforming other transformation rules.
Verbatim[expr] does not maintain expr in an unevaluated form.
See The Mathematica Book: Section 2.3.12.
See also: HoldPattern.