A more thorough explanation:

Definition: In all things; on all points.

Example: The lawyer argued that the defendant was guilty in omnibus, citing evidence from multiple witnesses and forensic reports.

Explanation: The example illustrates the use of "in omnibus" in a legal context, where the lawyer is stating that the defendant is guilty on all points or aspects of the case. The phrase can also be used in other contexts, such as business or personal matters, to indicate a comprehensive or all-encompassing approach.