| Underwater sound detectors | 26 |
| Underwater slitherers | 21 |
| Underwater slitherer | 20 |
| Underwater shocker | 18 |
| Underwater search vessel | 24 |
| Underwater search device | 24 |
| Underwater sandbank | 19 |
| Underwater salvager, e.g. | 25 |
| Underwater ridge | 16 |
| Underwater research vessel | 26 |
| Underwater research site | 24 |
| Underwater ray | 14 |
| Underwater propeller? | 21 |
| Underwater projectile | 21 |
| Underwater predator | 19 |
| Underwater power source? | 24 |
| Underwater plant | 16 |
| Underwater pit residents | 24 |
| Underwater peak | 15 |
| Underwater obstacle | 19 |
| Underwater object locater | 25 |
| Underwater naval habitat | 24 |
| Underwater missile | 18 |
| Underwater military guy | 23 |
| Underwater menace? | 18 |
| Underwater menace | 17 |
| Underwater man | 14 |
| Underwater lateral surface? | 27 |
| Underwater knoll | 16 |
| Underwater killer | 17 |
| Underwater ink stains? | 22 |
| Underwater ink squirter | 23 |
| Underwater herbivore | 20 |
| Underwater hazards | 18 |
| Underwater hazard marker | 24 |
| Underwater hazard | 17 |
| Underwater habitat | 18 |
| Underwater growths | 18 |
| Underwater growth | 17 |
| Underwater gear | 15 |
| Underwater forest plant | 23 |
| Underwater fishing aid | 22 |
| Underwater fisherman | 20 |
| Underwater finder | 17 |
| Underwater films? | 17 |
| Underwater families | 19 |
| Underwater explosive | 20 |
| Underwater explorer | 19 |
| Underwater experiment site | 26 |
| Underwater excavation machine | 29 |
| Underwater escape mechanism | 27 |
| Underwater entertainment? | 25 |
| Underwater England/France connection | 36 |
| Underwater electricity source | 29 |
| Underwater eggs | 15 |
| Underwater directors | 20 |
| Underwater detector? | 20 |
| Underwater detector | 19 |
| Underwater detection technique | 30 |
| Underwater detection systems | 28 |
| Underwater detection system | 27 |
| Underwater detection instruments | 32 |
| Underwater detection device | 27 |
| Underwater deposit | 18 |
| Underwater current generator | 28 |
| Underwater creature whose males give birth | 42 |
| Underwater craft, briefly | 25 |
| Underwater craft | 16 |
| Underwater concrete depositor | 29 |
| Underwater cave dweller | 23 |
| Underwater breathing organs | 27 |
| Underwater breathing gear | 25 |
| Underwater breathing apparatus? | 31 |
| Underwater breathing apparatus | 30 |
| Underwater breathing aids | 25 |
| Underwater breathing aid | 24 |
| Underwater breather | 19 |
| Underwater bloodsucker | 22 |
| Underwater beeper | 17 |
| Underwater army dangers? | 24 |
| Underwater apparatus | 20 |
| Underwater activity | 19 |
| Underwater acronym | 18 |
| Underwater "wolf pack" | 32 |
| Undervalued | 11 |
| Undervalue. | 11 |
| Underutilize | 12 |
| Undertow single | 15 |
| Undertook | 9 |
| Undertones | 10 |
| Undertone | 9 |
| Underthing that's part of a bleeped phrase? | 47 |
| Undertakings | 12 |
| Undertaking, in Britain | 23 |
| Undertaking | 11 |
| Undertakes, as risk | 19 |
| Undertakes without permission | 29 |
| Undertakes | 10 |
| Undertakers | 11 |
| Undertaker, usually | 19 |