| Uninvited picnic guests | 23 |
| Uninvited wedding guest | 23 |
| Uninviting to a vegan, e.g. | 27 |
| Union and others: Abbr. | 23 |
| Union at the docks: Abbr. | 25 |
| Union based in Detroit, Mich. | 29 |
| Union boss who went missing | 27 |
| Union bosses' bunks? | 24 |
| Union broken by Pres. Reagan | 28 |
| Union Civil War general | 23 |
| Union collectors' items | 27 |
| Union commander at Gettysburg | 29 |
| Union contract provision | 24 |
| Union contract subject | 22 |
| Union disbanded by Reagan | 25 |
| Union former in 1993: Abbr. | 27 |
| Union founded in '35 | 24 |
| Union founded in 1905: Abbr. | 28 |
| Union general at Antietam | 25 |
| Union general at Gettysburg | 27 |
| Union general at Shiloh | 23 |
| Union general's kin | 23 |
| Union in a 1955 merger | 22 |
| Union in Chicago, e.g. | 22 |
| Union in D.C., for example | 26 |
| Union in Detroit, initially | 27 |
| Union in the European capital | 29 |
| Union inits. starting in 1886 | 29 |
| Union leader John L. ___ | 24 |
| Union leaders, perhaps? | 23 |
| Union led by Richard Trumka | 27 |
| Union mem. since 2/14/1912 | 26 |
| Union member at times | 22 |
| Union member since 1803 | 23 |
| Union member since 1820 | 23 |
| Union member since 1850 | 23 |
| Union member since 1890 | 23 |
| Union member since 1896 | 23 |
| Union member's payment | 26 |
| Union mems. until 1991 | 22 |
| Union negotiation topics | 24 |
| Union opponent, briefly | 23 |
| Union Pacific and BNSF | 22 |
| Union Pacific et al.: Abbr. | 27 |
| Union Pacific headquarters | 26 |
| Union Pacific terminus | 22 |
| Union requirement, maybe? | 25 |
| Union Sq. and Times Sq. | 23 |
| Union steward's domain | 26 |
| Union with 2 1/2 mil. members | 29 |
| Union with 2.7 mil. members | 27 |
| Union with 3.2 mil. members | 27 |
| Union's collection | 22 |
| Union's contract demand? | 28 |
| Union's minimum wage | 24 |
| Union, in D.C., for one | 23 |
| Union, in L.A. or D.C. | 22 |
| Union-management agcy. | 22 |
| Union-mgmt. dispute watchdog | 28 |
| Union-vote facilitator | 22 |
| Unionize, so to speak? | 22 |
| Unique 1960's TV star | 25 |
| Unique identifier for dogs | 26 |
| Unique items or people | 22 |
| Unique object or person | 23 |
| Unique person or thing | 22 |
| Unique person, informally | 25 |
| Unique shades at the stable? | 28 |
| Unique stretch in time | 22 |
| Unique thing or person | 22 |
| Unisex cologne since 1994 | 25 |
| Unisex designer cologne | 23 |
| Unisex gown of old Greece | 25 |
| Unisex Shakespearean play? | 26 |
| Unisphere, essentially | 22 |
| Unit amount of sunlight seen? | 29 |
| Unit at the top of a browser | 28 |
| Unit by unit, in succession | 27 |
| Unit dosage of radiation | 24 |
| Unit equal to 10,000 gauss | 26 |
| Unit equal to 15.432 grains | 27 |
| Unit equal to 200 milligrams | 28 |
| Unit equaling 200 milligrams | 28 |
| Unit equaling 43,560 sq. ft. | 28 |
| Unit for a frequent flier | 25 |
| Unit for an electrician | 23 |
| Unit for Chris or Martina | 25 |
| Unit for dangerous situations | 29 |
| Unit for modern processors | 26 |
| Unit in a Brownian model | 24 |
| Unit in a geology book | 22 |
| Unit in a multiunit building | 28 |
| Unit in a physics textbook | 26 |
| Unit in a radar receiver | 24 |
| Unit in many a sentence | 23 |
| Unit in the c.g.s. system | 25 |
| Unit in una zona residencial | 28 |
| Unit indicated by " | 24 |
| Unit indicated by an omega | 26 |
| Unit indicating loudness | 24 |