- HBOMB
- Big boom maker
- Cold War threat
- Nuclear weapon
- Eniwetok device
- Eniwetok test device
- Big bang source?
- It's tested in a VERY remote area
- Project Brass Ring was a 1950 project meant to deliver one on a drone
- The element fermium was discovered in the aftermath of the first one
- Thermonuclear exploder
- Eniwetok test subject
- Mushroom cloud maker
- Thermonuclear explosive
- Cold war concern
- Nuclear device
- Weapon of mass destruction
- Blast maker, informally
- Big blast
- Subject of a '52 test
- Oppenheimer opposed it
- Ivy Mike test weapon
- 1950s WMD
- Godzilla creator, in the story
- Its testing awakened Godzilla ... and what's dropped, facetiously, into five puzzle answers
- Weapon in a 1952 test
- Cold War concern ... and what created 20-, 32-, 40- and 55-Across?
- Subject of '60s tests and protests
- Fusion weapon
- Edward Teller's legacy
- Mushroom cloud former, for short
- Big blast producer, for short
- The big question mark.
- A. E. C. project.
- Its power is measured in megatons.
- Fearsome weapon.
- Type of missile.
- Eniwetok first
- Powerful weapon
- Exploder at Eniwetok: 1952
- Frightful force
- SALT concern
- Cold War concern, for short
- The first one went off in 1952
- Thermonuclear blast maker
- Weapon since 1952
- It was tested on Bikini, 1954
- *Weapon first tested in '52
- 16-Across concern, briefly
- Certain W.M.D.
- U.S.S.R.'s Big Ivan, e.g.
- Test ban subject, briefly
- Big bang maker, informally
- Eniwetok blaster, informally
- Weapon of mass destruction, informally
- Bikini blast
- Cold war specter
- Nuclear threat
- Thermonuclear explosive (Abbr.)
- Big bang, and it's no theory
- A nuclear weapon
- Big bang maker, and it's no theory
- Explosive development of 1951
- Big bang maker
- Bikini demolisher
- Thermonuclear explosive, briefly
- Weapon since '52
- Big boomer
- Truman announced its development in January 1950