| One of Noah's boys | 22 |
| One of Noah's descendants | 29 |
| One of Noah's sons | 22 |
| One of Nod's two partners | 29 |
| One of numerous childhood spots? | 32 |
| One of O'Brien's forerunners | 36 |
| One of Oberon's subjects | 28 |
| One of October's birthstones | 32 |
| One of Odin's wolves | 24 |
| One of old Hollywood's Big Five | 35 |
| One of Old's cars | 21 |
| One of Olds's cars | 22 |
| One of Omar's creations | 27 |
| One of Omar's three wishes | 30 |
| One of Omar's wishes | 24 |
| One of one hundred | 18 |
| One of one's dukes | 22 |
| One of only 10 players to have the three-year waiting period waived for | 71 |
| One of only three golfers who briefly kept Tiger Woods out of the World #1 spot between 1/11/1998 and 10/30/2010 | 112 |
| One of only two presidents with two Ivy League degrees | 54 |
| One of only two S.A. countries that don't border Brazil | 59 |
| One of only two women on Rolling Stone's list of "100 Greatest Guitarists of All Time" | 100 |
| One of OPEC's charter members | 33 |
| One of OPEC's founders | 26 |
| One of Ophelia's flowers | 28 |
| One of Ophelia's herbs | 26 |
| One of Orion's pets | 23 |
| One of Orson's exes | 23 |
| One of over 1,250 restaurants, briefly | 38 |
| One of over 100 on a table | 26 |
| One of over 2,000,000 Cubans | 28 |
| One of over a dozen popes | 25 |
| One of Oxford's colleges | 28 |
| One of Ozzie and Harriet's boys | 35 |
| One of P-R-N-D-L | 16 |
| One of Pac-Man's pursuers | 29 |
| One of Pan's companions | 27 |
| One of Pan's foes | 21 |
| One of Pandora's finds | 26 |
| One of Paul Revere's message options | 40 |
| One of Paul Revere's signals | 32 |
| One of Pauline's adventures | 31 |
| One of Pavarotti's assets | 29 |
| One of Pétain's names | 28 |
| One of Penelope's 108 in the "Odyssey" | 52 |
| One of Perry's reporters | 28 |
| One of Perry's reporters at the Daily Planet | 48 |
| One of Perry's top reporters | 32 |
| One of Pete Rose's records | 30 |
| One of Peter Rabbit's siblings | 34 |
| One of Peter Rabbit's sisters | 33 |
| One of Peter's picks | 24 |
| One of Phoebe's friends | 27 |
| One of Pittsburgh's rivers | 30 |
| One of Pittsburgh's three | 29 |
| One of Pittsburgh's three rivers | 36 |
| One of Pizarro's captains who later crossed the Mississippi River | 69 |
| One of Plato's "Dialogues" | 40 |
| One of Plato's 35 dialogues | 31 |
| One of Plato's dialogues | 28 |
| One of Plato's pupils | 25 |
| One of Plato's topics | 25 |
| One of Poe's names | 22 |
| One of Poland's three most populous cities | 46 |
| One of Polly Adler's ilk | 28 |
| One of Polynesian-Melanesian descent | 36 |
| One of Pooh's friends | 25 |
| One of Pooh's hundred | 25 |
| One of Pooh's pals | 22 |
| One of Pop's cohorts | 24 |
| One of Pop's mates | 22 |
| One of Poseidon's attendants | 32 |
| One of Potter's professors | 30 |
| One of Pres. Carter's sisters | 33 |
| One of Princess Yasmin's names | 34 |
| One of Prometheus' brothers | 31 |
| One of Ptolemy's 48 | 23 |
| One of Ptolemy's 48 constellations | 38 |
| One of Ptolemy's constellations | 35 |
| One of Ptolemy's original 48 constellations | 47 |
| One of Ptolemy's original constellations | 44 |
| One of Puff Daddy's clothing labels | 39 |
| One of R.R.'s predecessors | 30 |
| One of R.W.R.'s titles | 26 |
| One of racially mixed ancestry | 30 |
| One of racing's "Big Three" | 41 |
| One of radio's Goldbergs | 28 |
| One of Ray Floyd's concerns | 31 |
| One of reality TV's "Guidettes" | 45 |
| One of Rebekah's boys | 25 |
| One of Rebekah's sons | 25 |
| One of Rebekah's twins | 26 |
| One of Reese's teammates | 28 |
| One of Renoir's fortes | 26 |
| One of Rhee's soldiers | 26 |
| One of Richard's veeps | 26 |
| One of Rin Tin Tin's successors | 35 |
| One of Rita's husbands | 26 |
| One of Robert Frost's daughters | 35 |
| One of Robin Hood's men | 27 |