- oaf
- oak
- oar
- oat
- oath
- oatmeal
- obesity
- obligation
- oblige
- obliterate
- oblivious
- obscure
- observation
- observe
- observer
- obsess
- obstacle
- obstetrics
- obstinate
- obstruct
- obstruction
- occasion
- occasional
- occult
- ocular
- odds
- odo(u)r
- offence(-se)
- offend
- offensive
- officinal
- officious
- offset
- omen
- ominous
- oncology
- onion
- opaque
- opera
- ophthalmology
- opiate
- opium
- opponent
- opportunity
- oppress
- oppression
- opt
- optical
- optics
- optimal
- optimism
- optimistic
- optimize
- optimum
- option
- optional
- optometrist
- orbit
- orchard
- orchestra
- ordeal
- organ
- organelle
- organic
- organism
- orient
- oriental
- orifice
- originality
- originate
- ornament
- ornamental
- orphan
- orthopedics
- osmosis
- osteoma
- ostrich
- otitis
- otorhinolaryngology
- outpatient
- outrageous
- outskirts
- oval
- ovary
- oven
- overactivity
- overall
- overcast
- overflow
- oversleeve
- overt
- overthrow
- overwhelm
- ovum
- oxide
- oyster
- ozone
大学英语考博单词单词大全〔O 〕课程包含97个英语单词词汇。