| Ulster Volunteer Force | Ulster Volunteer Force |
| Ulster Volunteers | Ulster Volunteer Force |
| Ulten | Ultimo |
| ultimate | ostateczny |
| Ultimate Nightmare | Inkub |
| ultimately | ostatecznie |
| ultimatum | ultimatum |
| ultimogeniture | ultimogenitura |
| Ultra High Definition Video | UHD |
| Ultra high molecular weight polyethylene | Dyneema |
| Ultra low frequency | ULF |
| Ultra short wave | UKF |
| Ultra-high-temperature processing | UHT |
| Ultra-light | Ultralight |
| Ultra-Mobile PC | Ultra-Mobile PC |
| Ultra-royalist | Ultrasi |
| Ultra-short wave | UKF |
| Ultra-wideband | Ultra wideband |
| ultrafilter | ultrafiltr |
| Ultrafiltration | Ultrafiltracja |
| Ultraist | Ultra |
| Ultraist movement | Ultraizm |
| Ultralight aviation | Ultralight |
| Ultramafic rock | Skały ultrazasadowe |
| Ultraproduct | Ultraprodukt |
| Ultras | Ultras |
| Ultrasauros | Ultrazaur |
| ultrasonic | ultradźwiękowy |
| Ultrasonic flow meter | Przepływomierz ultradźwiękowy |
| Ultrasonic motor | Silnik soniczny |
| Ultrasonic sound | Ultradźwięki |
| ultrasound | ultradźwięk |
| ultraviolet | ultrafioletowy |
| ultraviolet radiation | promieniowanie ultrafioletowe |
| Uluburun shipwreck | Uluburun |
| Ulugh Beg | Uług Beg |
| Uluru | Uluru |
| Ulus | Ułus |
| Ulva | Ulva |
| Ulvik | Ulvik |
| Ulvophyceae | Watkowe |
| Ulyanovsk | Uljanowsk |
| Ulyanovsk Oblast | Obwód uljanowski |
| Ulyanovskaya Mine disaster | Katastrofa górnicza w kopalni Uljanowskaja |
| Ulysses | Odyseusz |
| Ulysses S. Grant | Ulysses Grant |
| Ulúa River | Ulúa |
| Um er-Rasas | Umm ar-Rasas |
| Uma Thurman | Uma Thurman |
| Umag | Umag |
| Umag Open | Studena Croatia Open Umag |
| Umaglesi Liga | I liga gruzińska w piłce nożnej |
| umami | umami |
| Uman | Humań |
| Umar | Umar ibn al-Chattab |
| Umar II | Umar ibn Abd al-Aziz |
| Umayyad | Umajjadzi |
| Umbanda | Umbanda |
| Umbardacil | Telumehtar |
| umbel | baldach |
| umbellifer | selerowate |
| Umberto Boccioni | Umberto Boccioni |
| Umberto Caligaris | Umberto Caligaris |
| Umberto Eco | Umberto Eco |
| Umberto I of Italy | Humbert I |
| Umberto II of Italy | Humbert II |
| Umberto Nobile | Umberto Nobile |
| umbilicus | pępek |
| Umbozero | Umboziero |
| Umbozero Lake | Umboziero |
