| '50s nuclear experiment | 27 |
| '50s nuclear blast | 22 |
| ''This is only ___'' (radio message) | 52 |
| White Sands experiment | 22 |
| What this is only? | 18 |
| Underground explosion | 21 |
| Trinity event | 13 |
| Trial at Los Alamos | 19 |
| This is only ____ | 17 |
| Secret event of '45 | 23 |
| SALT I topic | 12 |
| Remotely monitored event, informally | 36 |
| Periodic radio signal | 21 |
| Outlawed explosion | 18 |
| Operation Trinity event | 23 |
| Operation Crossroads event, 1946 | 32 |
| Onetime Marshall Isl. event | 27 |
| Old fallout source | 18 |
| Nuke event, briefly | 19 |
| Nuclear trial, for short | 24 |
| Nuclear explosion | 17 |
| Nuclear event, in headlines | 27 |
| Nuclear event | 13 |
| Nevada blast | 12 |
| Mushroom producer | 17 |
| Mushroom maker, for short | 25 |
| Mushroom maker, briefly | 23 |
| Mushroom grower, for short? | 27 |
| Manhattan Project event | 23 |
| Los Alamos event | 16 |
| July 16, 1945, event | 20 |
| It might lead to a cloud formation, for short | 45 |
| It can lead to fallout, for short | 33 |
| Historically significant trial | 30 |
| Historic event on Bikini atoll, briefly | 39 |
| Historic 1940s event, for short | 31 |
| Event that could be seen as far away as Las Vegas in the '50s | 65 |
| Event in 1940s-'50s headlines | 33 |
| Event at Alamogordo: 1945 | 25 |
| Engage in ___ of wills | 22 |
| Defense initiative, for short | 29 |
| Controversial nuclear event | 27 |
| Controversial event | 19 |
| Controversial Bikini Atoll event | 32 |
| Controversial 50's event | 28 |
| Cold war-era blast, in headlines | 32 |
| Boomer experiment? | 18 |
| Bomb trial, briefly | 19 |
| Blast from the past? | 20 |
| Bikini's claim to fame | 26 |
| Bikini tryout | 13 |
| Bikini trial | 12 |
| Bikini experiment | 17 |
| Bikini event: 1946 | 18 |
| Bikini event, once | 18 |
| Bikini event, in old headlines | 30 |
| Bikini blowup, briefly | 22 |
| Bikini blowout, briefly | 23 |
| Bikini blowout in '46 | 25 |
| Bikini blast, informally | 24 |
| Big shock wave producer, briefly | 32 |
| Big blast, informally | 21 |
| Big blast producer | 18 |
| Atoll explosion | 15 |
| Alamogordo trial | 16 |
| Alamogordo event, 7/16/45 | 25 |
| Alamogordo event of July 1945 | 29 |
| Alamogordo blast | 16 |
| Alamagordo event | 16 |
| 1948 event dubbed "Operation Sandstone" | 49 |
| 1946 Bikini event | 17 |
| 1945 Alamogordo event, informally | 33 |
| 1945 Alamogordo event, briefly | 30 |
| 1940s Bikini blast, in brief | 28 |
| "Time is ___ of trouble": E. Dickinson | 48 |
| "Time is ___ of Trouble": Dickinson | 45 |
| "This is only ---!" | 29 |
| "This is only ___" (radio announcement) | 49 |
| "This is only ___" (part of an old TV message) | 56 |
| "This is only ___..." (radio phrase) | 46 |
| "This is only _____" | 30 |
| "This is only ___ ..." (emergency broadcast) | 54 |
| "This is only ---!" | 30 |
| "This is not ---" | 27 |
| "This is just __" | 27 |
| "This is __" | 22 |
| "This is ___ ..." (radio announcement) | 48 |
| "This has been ___..." | 32 |
| "This has been ___ ..." | 33 |
| "This has been __ . . ." | 34 |
| '50s headline event | 23 |
| ''This is only __'' | 35 |
| ''This is only ___!'' | 37 |
| ''This is only ___!'' | 38 |
| ''This is ___'' (radio broadcast line) | 54 |
| ''This is ___ of the emergency ...'' | 52 |
| __ of strength | 14 |
| Mushroom makers | 15 |
| Nuclear trials | 14 |
| Blasts from the past | 20 |