| Unmanned craft that makes targeted attacks | 42 |
| Unmanned NASA mission of the '70s | 37 |
| Unmanned space probe launched Aug. 20, 1977 | 43 |
| Unmanned sub that found the Titanic | 35 |
| Unmanned vehicle that found the Titanic | 39 |
| Unmanned vessel that found the Titanic | 38 |
| Unmanned, unsettling military flier | 35 |
| Unmarried partner, in modern lingo | 34 |
| Unmarried partner, to the Census Bureau | 39 |
| Unmoved audience member, metonymically | 38 |
| Unnamed source of a secret, playfully | 37 |
| Unnatural desire to eat chalk, ashes, etc. | 42 |
| Unnecessary business advice for a stripper? | 43 |
| Unnecessary person, on a double date | 36 |
| Unnecessary words cluttering wise sayings? | 42 |
| Unnerving subject of an IRS notice | 34 |
| Unnerving way to hand in your job application | 45 |
| Unnominated film featuring Inspector Clouseau? | 46 |
| Unnominated film with a corny plot? | 35 |
| Unnominated film with a fuzzy subject? | 38 |
| Unobtrusive, as a ringtone setting | 34 |
| Unoccupied Middle Easterner, as of last month | 45 |
| Unofficial, like some university degrees | 40 |
| Unoriginal order, with "the" | 38 |
| Unorthodox, untraditional leaders | 33 |
| Unpleasant alternatives, figuratively | 37 |
| Unpleasant but indispensable parts of a job | 43 |
| Unpleasant cause of being woken up | 34 |
| Unpleasant consequence, figuratively | 36 |
| Unpleasant obligation to move, in chess | 39 |
| Unpleasant way to catch one's spouse | 40 |
| Unpleasant, paved-over urban spaces | 35 |
| Unpopular animal in a china shop? | 33 |
| Unpopular classification, in the 60's | 41 |
| Unpopular ophthalmologist's implement? | 42 |
| Unpopular player at a blackjack table | 37 |
| Unpredictable "Mask" actor? | 37 |
| Unpremeditated homicide (nonsexist style) | 41 |
| Unprepared tourist's surprise | 33 |
| Unprepared, as a sprinter in the blocks | 39 |
| Unprosperous time, metaphorically | 33 |
| Unquestioned style, hiding urban transit | 40 |
| Unread part of a movie review, maybe | 36 |
| Unrealistically idealistic state | 32 |
| Unrealized 60's Boeing project | 34 |
| Unrealized gain on an investment | 32 |
| Unrealized hit taken on an investment | 37 |
| Unrecoverable investment expenses | 33 |
| Unreliable communication method (h) | 35 |
| Unremarkable batting performance | 32 |
| Unrepentant individual, Biblically | 34 |
| Unrepentant response to an accusation | 37 |
| Unrestrained expression of emotion | 34 |
| Unrestrained Kentucky Derby entrant? | 36 |
| Unrewarding career, as coined by Douglas Coupland | 49 |
| Unrhymed poetry, usually in iambic pentameter | 45 |
| Unsafe thing in a room full of rocking chairs? | 46 |
| Unsanctioned class communicators | 32 |
| Unsanctioned workplace demonstration | 36 |
| Unsatisfied person's request | 32 |
| Unsatisfying reply to a question | 32 |
| Unsatisfying response to "Why?" | 41 |
| Unscheduled appointment book column | 35 |
| Unscientific means of getting results | 37 |
| Unscrambles a secret transmission | 33 |
| Unseal surreptitiously, as an envelope | 38 |
| Unsealed bottle at the perfume counter | 38 |
| Unseen "Fiddler on the Roof" tyrant | 45 |
| Unseen "Frasier" character | 36 |
| Unseen "Mork & Mindy" character | 45 |
| Unseen "Peanuts" character | 36 |
| Unseen character in a Beckett play | 34 |
| Unseen disaster waiting to happen | 33 |
| Unseen fairy in "Peter Pan" | 37 |
| Unseen title character in a Beckett play | 40 |
| Unselfish participant, or a mercantile harbor | 45 |
| Unsettled feelings, in Frankfurt | 32 |
| Unsigned band's rehearsal space | 35 |
| Unsigned bands' tour transport? | 35 |
| Unsolicited manuscripts, informally | 35 |
| Unsophisticated dullard, in slang | 33 |
| Unsophisticated, narrow-minded traits | 37 |
| Unspeaking member of the Seven Dwarfs | 37 |
| Unspectacular, unsuccessful batted ball? | 40 |
| Unspoken 'I don't know' | 35 |
| Unstable particles with great mass | 34 |
| Unstable situation, metaphorically | 34 |
| Unsubscribes, with "out" | 34 |
| Unsubtle public consumption disguise | 36 |
| Unsuccessful '70s-'80s cause | 36 |
| Unsuccessful '80s gridiron org. | 35 |
| Unsuccessful 1980s Apple computer | 33 |
| Unsuccessful 2020 Olympics contender | 36 |
| Unsuccessful apartment hunter's feeling? | 44 |
| Unsuccessful batter's intro? | 32 |
| Unsuccessful candidate in the 2004 primaries | 44 |
| Unsuitable for bluebloods, in England | 37 |
| Unsuitable for the squeamish, perhaps | 37 |
| Unsure one's question, perhaps | 34 |
| Unsustainable but trendy fuel source | 36 |