To stop; check: a brake that automatically arrests motion; arrested the growth of the tumor. To seize and hold under the authority of law. To capture and hold briefly (the attention, for example); engage. To undergo cardiac arrest: The patient arrested en route to the hospital. The act of detaining in legal custody: the arrest of a criminal suspect. The state of being so detained: a criminal under arrest. A device for stopping motion, especially of a moving part. The act of stopping or the condition of being stopped.