| Operating without ___ | 21 |
| Operating with ulterior motives | 31 |
| Operating with efficiency | 25 |
| Operating system, abbr. | 23 |
| Operating system whose code names are confections | 49 |
| Operating system that doesn't do Windows? | 45 |
| Operating system since the '60s | 35 |
| Operating system since 1969 | 27 |
| Operating system option | 23 |
| Operating system on many Internet servers | 41 |
| Operating system for PCs | 24 |
| Operating system developed by AT&T originally | 49 |
| Operating system developed at Bell Labs | 39 |
| Operating system designed by AT&T employees | 47 |
| Operating system choice | 23 |
| Operating system between Puma and Panther | 41 |
| Operating system before Windows | 31 |
| Operating system | 16 |
| Operating space | 15 |
| Operating simultaneously | 24 |
| Operating room? | 15 |
| Operating room substance, once | 30 |
| Operating room request | 22 |
| Operating room number? | 22 |
| Operating room necessities | 26 |
| Operating room item | 19 |
| Operating room insert | 21 |
| Operating room helper | 21 |
| Operating room devices | 22 |
| Operating room covers | 21 |
| Operating room assistant | 24 |
| Operating room apparel | 22 |
| Operating room aide | 19 |
| Operating room | 14 |
| Operating profitably | 20 |
| Operating procedures: Abbr. | 27 |
| Operating procedures (abbr.) | 28 |
| OPERATING PHYSICIAN HAS TROUBLE WITH STATIC CLING! | 50 |
| Operating periods | 17 |
| Operating in either of two ways | 31 |
| Operating handle | 16 |
| Operating expenses | 18 |
| Operating expense? | 18 |
| Operating conditions | 20 |
| Operating automatically | 23 |
| Operating at peak capacity | 26 |
| Operating at maximum | 20 |
| Operating at capacity | 21 |
| Operating at a profit | 21 |
| Operating at a loss | 19 |
| Operating alone | 15 |
| Operating | 9 |
| Operatic voices | 15 |
| Operatic voice | 14 |
| Operatic vocal solo | 19 |
| Operatic villains, often | 24 |
| Operatic type | 13 |
| Operatic twosome | 16 |
| Operatic tune | 13 |
| Operatic Trojan princess | 24 |
| Operatic tour de force | 22 |
| Operatic toast of two continents | 32 |
| Operatic texts | 14 |
| Operatic text | 13 |
| Operatic tenor ___ Alagna | 25 |
| Operatic tenor Vickers | 22 |
| Operatic temptress | 18 |
| Operatic superstar | 18 |
| Operatic stars | 14 |
| Operatic star | 13 |
| Operatic spear carrier, for short | 33 |
| Operatic soprano Netrebko | 25 |
| Operatic soprano Marilyn | 24 |
| Operatic soprano Gluck | 22 |
| Operatic soprano Geraldine | 26 |
| Operatic soprano from N.Y.C. | 28 |
| Operatic songs | 14 |
| Operatic song for one | 21 |
| Operatic song | 13 |
| Operatic solos | 14 |
| Operatic soloist | 16 |
| Operatic solo andrecitative | 28 |
| Operatic solo about a fur coat | 30 |
| Operatic solo | 13 |
| Operatic slave girl | 19 |
| Operatic slave | 14 |
| Operatic singing style | 22 |
| Operatic singer Pinza | 21 |
| Operatic singer on a sofa? | 26 |
| Operatic singer and actress Alberghetti | 39 |
| Operatic Simon | 14 |
| Operatic showstoppers | 21 |
| Operatic showstopper | 20 |
| Operatic show-stopper | 21 |
| Operatic sets | 13 |
| Operatic selection | 18 |
| Operatic ruler | 14 |
| Operatic role | 13 |
| Operatic rendition | 18 |
| Operatic recitative | 19 |