| observation deck | 6.39 | An observation deck will be near the top. | ||
| observation tower | 2.50 | The army built an observation tower on the top of the building. | ||
| observation point | 2.17 | On Sunday and today, rebel Serbs attacked two observation points. | ||
| observation mission | 1.32 | He is also due to inspect the UN observation mission along the Iraq-Kuwait border. | ||
| observation platform | 0.79 | The railing curves out near the observation platform. | ||
| observation satellite | 0.72 | The picture will be completed by US observation satellites. | ||
| observation statement | 0.72 | Even this most basic of observation statements involves theory, and is fallible. | ||
| observation team | 0.72 | Ballot box irregularities were reported by Asian observation teams. | ||
| observation area | 0.59 | A woman pushed a baby carriage through the observation area. | ||
| observation plane | 0.46 | No need for surveillance cameras and observation planes. | ||
| observation room | 0.46 | He said he was in and out of the observation room after that. | ||
| observation window | 0.46 | Hippos in a pond can be watched from an underwater observation window. | ||
| observation helicopter | 0.39 | U.S. officials stressed that the unarmed observation helicopter was on a routine mission. | ||
| observation site | 0.39 | Thursday, the observation site was moved to another location several blocks away. | ||
| observation post | 0.33 | He was to help set up artillery observations posts. | ||
| observation unit | 0.33 | It shows him touring an electoral observation unit. | ||
| observation aircraft | 0.26 | Two army pilots die when their military observation aircraft crashes. | ||
| observation committee | 0.26 | It also stipulates the creation of a ceasefire observation committee. | ||
| observation force | 0.26 | On Tuesday, Secretary of State Colin Powell reiterated U.S. opposition to an international observation force. | ||
| observation ship | 0.26 | He said they appeared to be observation ships, but their activities were unclear. |