| ___ number (speed measure) | 26 |
| ___ number (speed ratio) | 24 |
| ___ number on | 13 |
| ___ number on (mentally abuses) | 31 |
| ___ number on (mess up) | 23 |
| ___ number on (psyched out) | 27 |
| ___ number on (treats badly) | 28 |
| ___ number on (unnerve) | 23 |
| ___ Nung, legendary Chinese emperor | 35 |
| ___ Nurmi, nine-time track gold medalist in 1920s Olympics | 58 |
| ___ Nurmi, the Flying Finn | 26 |
| ___ nut | 7 |
| ___ nut (caffeine source) | 25 |
| ___ nut (narcotic Asian leaf) | 29 |
| ___ nut (wheel fastener) | 24 |
| ___ nutshell | 12 |
| ___ nutshell (succinctly) | 25 |
| ___ o menos (basically, in Spanish) | 35 |
| ___ o' livin' | 21 |
| ___ o' Shanter | 18 |
| ___ o'clock scholar | 23 |
| ___ O'Hara, Bill Bixby's role on "My Favorite Martian" | 72 |
| ___ O'More, name of three Irish chieftains | 46 |
| ___ O'Neill | 15 |
| ___ O'Neill Chaplin | 23 |
| ___ O's (chocolaty cereal) | 30 |
| ___ O's (Post cereal) | 25 |
| ___ o'Shanter | 17 |
| ___ O'Shea, music-hall star | 31 |
| ___ oak | 7 |
| ___ oats (cereal ingredient) | 28 |
| ___ Obama (controversial kitsch item) | 37 |
| ___ Obama (novelty gift) | 24 |
| ___ Obispo | 10 |
| ___ oblige | 10 |
| ___ oblongata (brain part) | 26 |
| ___ obscure (chiaroscuro) | 25 |
| ___ Observatory | 15 |
| ___ Observatory, home of the world's largest single-aperture radio telescope | 80 |
| ___ obstante | 12 |
| ___ obstat (error-free) | 23 |
| ___ occasion | 12 |
| ___ occasion (never) | 20 |
| ___ occasions (seldom) | 22 |
| ___ Ocean, Julia Roberts's "Ocean's Eleven" role | 66 |
| ___ Octavius ("Spider Man" villain) | 45 |
| ___ Octavius ("Spider-Man" villain Doc Ock's "real" name) | 81 |
| ___ Octavius (Spider-Man villain) | 33 |
| ___ Octubre (nickname of Orlando Hernández after he went 8-0 to start his postseason career) | 95 |
| ___ oculi (muscle of the eye) | 29 |
| ___ odds (alienate) | 19 |
| ___ odds (antagonize) | 21 |
| ___ odds on | 11 |
| ___ Oder (German river) | 23 |
| ___ of | 6 |
| ___ of (addressing term) | 24 |
| ___ of (collides with) | 22 |
| ___ of (free) | 13 |
| ___ of (get by cajolery) | 24 |
| ___ of (gets too big for) | 25 |
| ___ of (happen to) | 18 |
| ___ of (having just sold) | 25 |
| ___ of (impressed) | 18 |
| ___ of (in a way) | 17 |
| ___ of (in control) | 19 |
| ___ of (knowing about) | 22 |
| ___ of (near) | 13 |
| ___ of (never before known) | 27 |
| ___ of (rather than) | 20 |
| ___ of (rather) | 15 |
| ___ of (utilize) | 16 |
| ___ of (with reference to) | 26 |
| ___ of 1812 | 11 |
| ___ of a coin | 13 |
| ___ of a Down | 13 |
| ___ of a gun | 12 |
| ___ of a kind | 13 |
| ___ of a piece | 14 |
| ___ of a sea cook | 17 |
| ___ of Abraham | 14 |
| ___ of admissions | 17 |
| ___ of affairs | 14 |
| ___ of all | 10 |
| ___ of all right | 16 |
| ___ of allegiance | 17 |
| ___ of America | 14 |
| ___ of America (Boston) | 23 |
| ___ of approval | 15 |
| ___ of Aquarius | 15 |
| ___ of Aquitaine (Henry II's queen) | 39 |
| ___ of Aquitaine, Henry II's wife | 37 |
| ___ of Arc | 10 |
| ___ of armor | 12 |
| ___ of arms | 11 |
| ___ of Artemis | 14 |
| ___ of assistance (search warrant) | 34 |
| ___ of Attalos (Greek museum site) | 34 |
| ___ of August (1st of that month) | 33 |
| ___ of Austria (mother of Louis XIV) | 36 |
| ___ of averages | 15 |