| Unison cheer (1894) | 19 |
| Unisonally | 10 |
| Unisphere, e.g. | 15 |
| Unisphere, essentially | 22 |
| Unit | 4 |
| Unit a little longer than an arm's length | 45 |
| Unit amount of sunlight seen? | 29 |
| Unit at a pub | 13 |
| Unit at a reactor | 17 |
| Unit at a state park | 20 |
| Unit at Harvard | 15 |
| Unit at the Olympics | 20 |
| Unit at the top of a browser | 28 |
| Unit at Wimbledon | 17 |
| Unit attachment | 15 |
| Unit by unit, in succession | 27 |
| Unit charge | 11 |
| Unit circle radius | 18 |
| Unit cohesion | 13 |
| Unit cost word | 14 |
| Unit dosage of radiation | 24 |
| Unit equal to 0.338 fluid ounce | 31 |
| Unit equal to 10,000 gauss | 26 |
| Unit equal to 100,000,000 maxwells | 34 |
| Unit equal to 15.432 grains | 27 |
| Unit equal to 200 milligrams | 28 |
| Unit equal to 61.02 cubic inches | 32 |
| Unit equal to one billion gammas | 32 |
| Unit equal to one candela per square meter | 42 |
| Unit equal to one coulomb per second | 36 |
| Unit equal to one millionth of a meter | 38 |
| Unit equaling 10,000 square meters | 34 |
| Unit equaling 200 milligrams | 28 |
| Unit equaling 43,560 sq. ft. | 28 |
| Unit equivalent to 3.26 light years | 35 |
| Unit equivalent to 550 foot-pounds per second | 45 |
| Unit fighting vice | 18 |
| Unit follower | 13 |
| Unit for a chairmaker | 21 |
| Unit for a duel | 15 |
| Unit for a frequent flier | 25 |
| Unit for a lorry | 16 |
| Unit for an electrician | 23 |
| Unit for Borg | 13 |
| Unit for Chris or Martina | 25 |
| Unit for Connors | 16 |
| Unit for dangerous situations | 29 |
| Unit for Drake | 14 |
| Unit for Lacoste | 16 |
| Unit for Lendl | 14 |
| Unit for light bulbs | 20 |
| Unit for Louis XIV | 18 |
| Unit for measuring flow of light | 32 |
| Unit for modern processors | 26 |
| Unit for My Son John | 20 |
| Unit for nukes | 14 |
| Unit for Pearl White | 20 |
| Unit for Shakespeare | 20 |
| Unit for Steve Cram | 19 |
| Unit from Mars? | 15 |
| Unit from the Greek for "work" | 40 |
| Unit having two or more battalions | 34 |
| Unit in a "Mary Poppins" song | 39 |
| Unit in a block | 15 |
| Unit in a Brownian model | 24 |
| Unit in a case | 14 |
| Unit in a geology book | 22 |
| Unit in a gym | 13 |
| Unit in a gym workout | 21 |
| Unit in a joule | 15 |
| Unit in a multiunit building | 28 |
| Unit in a physics textbook | 26 |
| Unit in a plan | 14 |
| Unit in a radar receiver | 24 |
| Unit in a terrorist organization | 32 |
| Unit in a tray at the register | 30 |
| Unit in acoustics | 17 |
| Unit in an erg's definition | 31 |
| Unit in astronomy | 17 |
| Unit in electricity | 19 |
| Unit in gemology | 16 |
| Unit in history class | 21 |
| Unit in linguistics | 19 |
| Unit in many a sentence | 23 |
| Unit in measuring population density | 36 |
| Unit in physics | 15 |
| Unit in realty | 14 |
| Unit in tennis | 14 |
| Unit in the c.g.s. system | 25 |
| Unit in the definition of surface tension | 41 |
| Unit in una zona residencial | 28 |
| Unit in verse | 13 |
| Unit indicated by " | 24 |
| Unit indicated by an omega | 26 |
| Unit indicating loudness | 24 |
| Unit inserted through the vagina, briefly | 41 |
| Unit involved in a shell game? | 30 |
| Unit measured by a gauge | 24 |
| Unit measuring loudness | 23 |
| Unit named after the inventor of the telephone | 46 |