| Underpass drainage channels | 27 |
| Undermines, as support | 22 |
| Underminer of principles | 24 |
| Undermine, as confidence | 24 |
| Underlying system of beliefs | 28 |
| Underlying form of a word | 25 |
| Underlying explanation | 22 |
| Underlings follow them | 22 |
| Underling's assignment | 26 |
| Underling's acquiescence | 28 |
| Underling of the 11th century | 29 |
| Underling of Fearless Leader | 28 |
| Underlined text, perhaps | 24 |
| Underhanded, to put it nicely | 29 |
| Underhanded or duplicitous | 26 |
| Underhanded course of action | 28 |
| Underhanded commercial ploy | 27 |
| Underhanded change, slangily | 28 |
| Underhanded activities | 22 |
| Underhand arrest maneuver | 25 |
| Underground-railroad cargo | 26 |
| Underground worker, perhaps | 27 |
| Underground water tank | 22 |
| Underground water sources | 25 |
| Underground water source | 24 |
| Underground water carrier | 25 |
| Underground transportation | 26 |
| Underground transport systems | 29 |
| Underground supporter? | 22 |
| Underground storage spot | 24 |
| Underground sources of income | 29 |
| Underground rock source | 23 |
| Underground rider, probably | 27 |
| Underground rapper's demo | 29 |
| Underground rapper ___ Rock | 27 |
| Underground Railroad user | 25 |
| Underground Railroad traveler | 29 |
| Underground railroad leader | 27 |
| Underground Pueblo chamber | 26 |
| Underground protection | 22 |
| Underground plant supports | 26 |
| Underground plant parts | 23 |
| Underground plant part | 22 |
| Underground petroleum source | 28 |
| Underground passageway | 22 |
| Underground part of a plant | 27 |
| Underground music genre | 23 |
| Underground movement leader? | 28 |
| Underground molten rock | 23 |
| Underground missile site | 24 |
| Underground meeting place | 25 |
| Underground mag of the 1960s | 28 |
| Underground launch site | 23 |
| Underground installation | 24 |
| Underground infiltrator | 23 |
| Underground hip-hop release | 27 |
| Underground folklore creature | 29 |
| Underground explosions | 22 |
| Underground discoveries | 23 |
| Underground dance party | 23 |
| Underground crop storage area | 29 |
| Underground coal source | 23 |
| Underground burial site | 23 |
| Underground burial places | 25 |
| Underground blast, perh. | 24 |
| Underground artists, maybe | 26 |
| Underground art site in Spain | 29 |
| Undergraduate law deg. | 22 |
| Undergrads' degrees | 23 |
| Undergrad's bugbear | 23 |
| Undergrad degrees: Abbr. | 24 |
| Undergrad course, briefly | 25 |
| Undergrad course of study | 25 |
| Undergoing severe trials | 24 |
| Undergoes a transformation | 26 |
| Undergoes a chemical change | 27 |
| Undergo without yielding | 24 |
| Undergo training, perhaps | 25 |
| Undergo natural selection | 25 |
| Undergo gradual change | 22 |
| Undergo chemical change | 23 |
| Undergo a chemical change | 25 |
| Undergo a change of habit? | 26 |
| Undergarment, for short | 23 |
| Undergarment specification | 26 |
| Undergarment fitting device? | 28 |
| Underfootings for dignitaries | 29 |
| Underfooting for Fleming | 24 |
| Underdogs' victories | 24 |
| Underdogs may beat them | 23 |
| Underdog's win, e.g. | 24 |
| Underdog's victory | 22 |
| Underdog's fastener? | 24 |
| Underdog's achievement | 26 |
| Underdog with a chance | 22 |
| Underdog winner over T.E.D. | 27 |
| Underdog playoffs participant | 29 |
| Underdog in a certain ring | 26 |
| Underdeveloped nations | 22 |
| Underdeveloped countries | 24 |