| Oil ministers' grp. | 23 |
| Oil ministers' org. | 23 |
| Oil name from long ago | 22 |
| Oil obtained from flowers | 25 |
| Oil of rose petals, e.g. | 24 |
| Oil of wintergreen is one | 25 |
| Oil of wintergreen source | 25 |
| Oil of wintergreen, e.g. | 24 |
| Oil of ___ (cosmetics brand) | 28 |
| Oil on a wall, for example | 26 |
| Oil or vinegar container | 24 |
| Oil painter's mixture | 25 |
| Oil partner in soapmaking | 25 |
| Oil Patch installation | 22 |
| Oil price-setting grp. | 22 |
| Oil producer's grp. | 23 |
| Oil sources for oil paint | 25 |
| Oil spill-monitoring org. | 25 |
| Oil tycoon Halliburton | 22 |
| Oil used in church rites | 24 |
| Oil well drilling gear | 22 |
| Oil well fire fighter of note | 29 |
| Oil well firefighter of note | 28 |
| Oil well firefighter Red | 24 |
| Oil well firefighter Red ___ | 28 |
| Oil well, for instance | 22 |
| Oil, in mechanic-speak | 22 |
| Oil-burning iron lantern | 24 |
| Oil-catching receptacle | 23 |
| Oil-drilling apparatus | 22 |
| Oil-drilling equipment | 22 |
| Oil-drilling structure | 22 |
| Oil-fire extinguisher Red ___ | 29 |
| Oil-producers' gp. | 22 |
| Oil-producers' org. | 23 |
| Oil-rich African country | 24 |
| Oil-rich Canadian province | 26 |
| Oil-rich non-OPEC nation | 24 |
| Oil-rich ruler, perhaps | 23 |
| Oil-rich South American basin | 29 |
| Oil-well capper Red ___ | 23 |
| Oil-well capper Red _____ | 25 |
| Oil-well firefighter Red | 24 |
| Oil-yielding fruit: Var. | 24 |
| Oil-yielding tree of C.A. | 25 |
| Oil-yielding tropical plant | 27 |
| Oil-yielding tropical tree | 26 |
| Oiler great ___ Tikkanen | 24 |
| Oilers' parent org. | 23 |
| Oilers' Skyreach ______ | 27 |
| Oilers, on NHL scoreboards | 26 |
| Oilman ___ P. Halliburton | 25 |
| Oils of a certain art form | 26 |
| Oils owned by the government? | 29 |
| Oils, ecclesiastically | 22 |
| Oily compound used in dyes | 26 |
| Oily hydrocarbon in petroleum | 29 |
| Oink : pig :: ___ : cow | 23 |
| Ointment of the ancients | 24 |
| Ointment package words | 22 |
| Ointment-yielding plant | 23 |
| Ointments for ducktails? | 24 |
| Ojibwa in a Longfellow poem | 27 |
| OK Cola drinker once, perhaps | 29 |
| OK Corral gunfighter Earp | 25 |
| OK for dieters, in ads | 22 |
| OK for the lactose-intolerant | 29 |
| OK setting in the summer | 24 |
| OK to watch, if mom agrees | 26 |
| OK, on a walkie-talkie | 22 |
| Okanagan's ____ pogo | 24 |
| Okanagan's____ pogo | 23 |
| Okay to put a price tag on | 26 |
| Okays from the kitchen? | 23 |
| Okefenokee dweller of comics | 28 |
| Okefenokee possum of comics | 27 |
| Okefenokee Swamp inhabitant | 27 |
| Okefenokee Swamp resident | 25 |
| Okinawa "OK" | 22 |
| Okinawa is one of these | 23 |
| Okinawa's largest city | 26 |
| Okla. before 1907, e.g. | 23 |
| Okla. city or Algonquian | 24 |
| Okla. City-to-Tulsa direction | 29 |
| Okla. from 1820 to 1840 | 23 |
| Okla., before 11/16/1907 | 24 |
| Okla., before statehood | 23 |
| Okla., from 1890 to 1907 | 24 |
| Oklahoma and West Virginia | 26 |
| Oklahoma City neighbor | 22 |
| Oklahoma city on the Arkansas | 29 |
| Oklahoma City setting: Abbr. | 28 |
| Oklahoma county or its seat | 27 |
| Oklahoma Native American | 24 |
| Oklahoma shipping supply? | 25 |
| Oklahoma Sooners rival | 22 |
| Oklahoma Sooners' rival | 27 |
| Oklahoma State U. site | 22 |
| Oklahoma to Kentucky dir. | 25 |
| Oklahoma tribal member | 22 |