| 5000 Vocabulary List for Visiting Scholars in the USA - Page 381 | |||
| Word | Type | Used in a Sentence | Synonym |
| opponent | noun | My opponent said he would not come. | rival |
| opportunity | noun | This is a wonderful opportunity. | chance |
| oppose | verb | We will oppose the new building. | fight against |
| opposite | adj. | We were on opposite sides of the room. | different |
| noun | The truth was the opposite. | contrary | |
| prep. | We parked the car opposite the bank. | facing | |
| oppress | verb | We must never oppress the people. | subjugate |
| optical | adj. | It was an optical illusion. | visual |
| optimism | noun | We will retain our optimism. | hopefulness |
| optimistic | adj. | She had an optimistic attitude. | hopeful |
| optional | adj. | The 8 cylinder engine is optional. | by choice |
| or | conj. | Do you want it hot or cold? | choice of |
| conj. | Bring me two or three copies. | shows uncertainty | |
| conj. | Your answer is either bad or clever. | indicates choice | |