| Rating | Solver | Clue |
|---|---|---|
| SABOTAGED | Undermined | |
| WEAKENED | Undermined | |
| DETERIORATED | Undermined | |
| DESTABILISED | Undermined | |
| COMPROMISED | Undermined | |
| DEMORALIZED | Undermined | |
| ERODED | Undermined (confidence) | |
| NIAGARA PERIOD | ...reater thickness of limestone, which is gradually undermined by the removal of the shale. See Chart of Geology. ... | |