O字母開頭的單詞或詞組(第5頁)：
- offline reader
- overpowering drug
- office-bearer
- otoneurology
- ode
- on the fly
- official holiday
- object machine
- outbid
- overgild
- oxygen balance
- outer face
- oxophenarsine hydrochloride
- omphalotribe
- oral groove
- oleum aethereum
- OCR
- operation interface command
- oral melanoma
- orangeade
- open-market
- outride
- orthocephaly
- ocelusal contact
- orbicular
- optical center of lens
- ossicle
- odoriferous glands
- oligopsony
- outlaid
- operation phase
- olfactory area
- ophthalmorrhea
- ochrodermia
- o carboxy cinnamic acid
- overseas remittance
- ophthalmosurgery
- opinions of accounting principles board
- omodynia
- ortho-para directing group