A more thorough explanation:

Definition: A criminal who has committed a violent crime or used force in trying to escape from custody.

Example: John is a dangerous criminal because he robbed a bank at gunpoint and injured a security guard while trying to escape.

This example illustrates the definition of a dangerous criminal as someone who has committed a violent crime and used force to escape from custody. John's actions caused harm to others and put their lives in danger, making him a dangerous criminal.