| An old glory | 12 |
| An old flame's pastime? | 27 |
| An old couple fell in it | 24 |
| An old Burmese capital | 22 |
| An Okla. native | 15 |
| An OK city? | 11 |
| An OK city | 10 |
| An ointment | 11 |
| An oily hydrocarbon | 19 |
| An oilman | 9 |
| An oil source | 13 |
| An oil producer | 15 |
| An oil man | 10 |
| An offspring of Juno | 20 |
| An official under Nero | 22 |
| An official language of the Northwest Territories | 49 |
| An official language of Sri Lanka | 33 |
| An official language of Singapore | 33 |
| An official language of Pakistan | 32 |
| An official lang. of Tonga | 26 |
| An official lang. of Switzerland | 32 |
| An official lang. of Malta | 26 |
| An official lang. of Kenya | 26 |
| An official lang. of Hong Kong | 30 |
| An official enforces it | 23 |
| An officer to avoid like the plague? | 36 |
| An officer below a lt. | 22 |
| An officer and a gentleman? | 27 |
| An offer to "en1arge your m@nhood," probably | 54 |
| An off-ramp may lead to one | 27 |
| An oenophile might detect a hint of this | 40 |
| An octopus' eight | 21 |
| An octopus has eight | 20 |
| An October birthstone | 21 |
| An octahedron has twelve | 24 |
| An ocelot has lots | 18 |
| An ocean: Abbr. | 15 |
| An ocean look? | 14 |
| An oc. | 6 |
| An obviously angry snake or cat | 31 |
| An observation game and an old TV series | 40 |
| An oboe, perhaps? | 17 |
| An oboe has two | 15 |
| An obnoxious person | 19 |
| An objet d'art | 18 |
| An objective of NOW | 19 |
| An objective for Sally? | 23 |
| An object of Bohr's research | 32 |
| An obese Lugosi? | 16 |
| An Obama girl | 13 |
| An Obama | 8 |
| An oath on it was once held to be inviolable | 44 |
| An Oakley | 9 |
| An O.K. Corral gunfighter | 25 |
| An O.K. | 7 |
| An O'Neill play | 19 |
| An O'Neill | 14 |
| An O'Neal | 13 |
| An O may symbolize one | 22 |
| An NFL team is named for one of his works | 41 |
| An NFL team | 11 |
| An NFL rivalry | 14 |
| An NFL Manning | 14 |
| An NCO, informally | 18 |
| An NCO | 6 |
| An N.Y.C. subway | 16 |
| An N.L.-er | 10 |
| An N.F.L. player | 16 |
| An N.C.O. | 9 |
| An N.B.A. team | 14 |
| An MIT grad. | 12 |
| An MIT grad, perhaps | 20 |
| An MGM lion | 11 |
| An M.V.P.: 1980 | 15 |
| An M.V.P.: 1970, 1972 | 21 |
| An M.V.P.: 1954, 1965 | 21 |
| An M.V.P. in 1980 | 17 |
| An M.I.T. degree | 16 |
| An LBJ daughter | 15 |
| An L.B.J. dog | 13 |
| An L.B.J. daughter | 18 |
| An L.B.J. beagle | 16 |
| An L.A. eleven | 14 |
| An Ivy, briefly | 15 |
| An Ivy Leaguer | 14 |
| An Ivy League jewel? | 20 |
| An Ivy | 6 |
| An itemized deduction | 21 |
| An Italian sauce | 16 |
| An Italian dish | 15 |
| An Italian cuisine | 18 |
| An Italian cheese | 17 |
| An isolate | 10 |
| An Isaac Bickerstaff | 20 |
| An irritated state | 18 |
| An Iroquois | 11 |
| An Iroquoian map | 16 |
| An Iroquoian | 12 |
| An Irish Literary Theatre founder | 33 |
| An iris, for short | 18 |