The definition of jailbreak is an escape from jail.(noun)
When a prisoner is able to escape his cell, this is an example of a jailbreak.
Jailbreak is defined as to modify the restraints or restrictions on a piece of technology so it does things the manufacturer did not intend it to do.(verb)
When you use a special program to unlock your iPhone so you can install whatever you want on it even if it wasn't meant to be installed, this is an example of a time you jailbreak your iPhone.
See jailbreak in Webster's New World College Dictionary
See jailbreak in American Heritage Dictionary 4
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