What is the meaning of Scram?

To leave in a hurry; to go away.

 A gun, firearm.

To shut down (a nuclear reactor or, by extension, some other thing) for safety reasons, usually because of an emergency.

Of a nuclear reactor or some other thing: to shut down, usually because of an emergency.

A shutdown of a nuclear reactor (or, by extension, some other thing), often done rapidly due to an emergency.

The device used to shut down a nuclear reactor; also, the button or switch used to initiate a shutdown.

To scratch (something) with claws or fingernails; to claw.

To mine for ore on a small scale, especially from mines previously been worked on where most of the ore is believed to have been removed.

A scratch, especially caused by claws or fingernails.

A mine previously worked on where most of the ore is believed to have been removed, but which is still being mined on a small scale.

Of one's body or limbs: to become numb or stiff due to cold, lack of movement, etc.

To be weakened by an accident, a disease, starvation, etc.

Source: wiktionary.org