| A | B |
|---|
| obsession | noun; a preoccupation; an idea, feeling, or impulse that a person cannot escape |
| obtuse | adjective; not sharp-edged or pointed; blunt; dull |
| omen | noun; a sign of what is to happen in the future |
| ominous | adjective; threatening; foreboding; sinister |
| opaque | adjective; not letting light through; not transparent; dark; hard to understand |
| oppressive | adjective; tyrannical; hard to take; physically or mentally distressing |
| optimistic | adjective; cheerful; expecting the best; inclined to look on the bright side |
| oratory | noun; skillful public speaking |
| orthodox | adjective; adhering to accepted beliefs, especially in religion; approved or conventional |
| ostracize | verb; to banish; to shut out or exclude from a group |
