| Unterklasse | subclass |
| Unterlassen | omission |
| unterlassen | stop |
| Untertasse | saucer |
| Überklasse | superclass |
| unter Wasser | underwater |
| Unterlage | base pad underlay document paper root-stock |
| Unterkleid | slip |
| Unterlagen | document |
| Unterwasser- | undersea |
| unterlaufen | eviscerate |
| Unterhaus | lower chamber lower house House of Commons |
| Unterhose | underpants pants briefs shorts |
| Unterlassung | omission |
| Unterlauf | lower reaches |
| Unterlippe | lower lip |
| Unterwäsche | underwear underclothes underclothing undergarments |
| unterdessen | in the meantime meanwhile |
| untertags | day daytime during |
| Interphase | interphase |