A U.S. missile

• Israel's Arrow, for one
• Anti missile missile (abbr.)
• Air defence sys
• A defensive missile designed to shoot down incoming intercontinental ballistic missiles
• SDI weapon
• "Star Wars" weapon: Abbr
• SALT subject, briefly
• Defence sys

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
1963, initialism (acronym) for anti-ballistic missile.