| Answer | Crossword Clue |
|---|---|
| DOMINOS | Pieces in a chain reaction |
| DOMINOES | Chain-reaction pieces |
| SETOFF | Spur, as a chain reaction |
| REARENDER | Result of a chain reaction accident, perhaps |
| initiators | A substance that starts a chain reaction |
| critical | (of a nuclear reactor or fuel) Maintaining a self-sustaining chain reaction |
