from The American Heritage® Dictionary of the English Language, 4th Edition
- intransitive v. To leave a scene at once; go abruptly.
- intransitive v. To shut down automatically. Used of a nuclear reactor.
- n. A rapid shutting down of a nuclear reactor, especially in an emergency.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- v. Get out of here; go away (frequently imperative).
- v. To abruptly insert the control rods of a nuclear reactor, usually in case of emergency shutdown.
- n. A rapid shutdown of a nuclear reactor
- n. Alternative spelling of SCRAM.
from the GNU version of the Collaborative International Dictionary of English
- intransitive v. to leave; to go away; used mostly as an impolite command to a person to go away from a specific location.
- transitive v. to shut down (a nuclear reactor) quickly, as in an emergency.
- n. the rapid shut down of a nuclear reactor, as in an emergency.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. leave immediately; used usually in the imperative form
Perhaps short for scramble.(American Heritage® Dictionary of the English Language, Fourth Edition)
Attested since 1928, originally as U.S. slang; either: (Wiktionary)
Back-formation from SCRAM, most etymology are likely backronyms. (Wiktionary)