- oak
- oath
- obscene
- obscure
- odor
- odour
- of the essence
- offset
- offspring
- olive
- on impulse
- on oath
- on the blink
- on the brink of
- on the threshold of
- on the verge of
- opaque
- oppress
- optimism
- optimum
- orient
- oriental
- orientation
- originate
- ornament
- orthodox
- outbreak
- outfit
- outrage
- overflow
- overhear
- overlap
- overpass
- overt
- overturn
- overwhelm
- overwhelming
- owl
- oxide
- ozone
大学英语六级单词单词大全〔O 〕课程包含40个英语单词词汇。