| Ubin Penrose | |
| ubiquinone | |
| udara | |
| udara | |
| uji dugaan | |
| uji fenolftalein | |
| uji hijau leucomalachite | |
| uji luminol | |
| uji mikrokristal | |
| uji natrium nitroprusside | |
| Ujian Mayer | |
| ukuran melingkar | |
| ultrasentrifuge | |
| ultrasonik | |
| umpan balik | |
| UNFO | |
| ungerade | |
| unit aritmatika / logika | |
| unit astronomi | |
| unit dasar | |
| unit dasar | |
| unit elektromagnetik | |
| unit elektrostatis | |
| unit geometri | |
| Unit Giorgi | |
| Unit Heaviside – Lorentz | |
| Unit kekaisaran | |
| unit kontrol | |
| unit pelengkap | |
| Unit pemrosesan utama | |
| unit radiasi | |
| unit turunan | |
| unit yang dirasionalisasi | |
| univalent | |
| UPS | |
| UPVC | |
| uraninite | |
| uranium | |
| uranium (IV) oksida | |
| uranium (VI) fluorida | |
| uranium habis | |
| uranium heksafluorida | |
| urasil | |
| urea | |
| urea nitrat | |
| Urey, Harold Clayton (1894–1981) | |
| uridine | |
| urutan peluruhan | |
| usia alam semesta | |
| usia bumi | |
| usia radioaktif | |
| USUS | |
| UV | |
