- ordnance depot
- operte
- open to error
- oil
- on top of
- OAPs
- out of the limelight
- on a weekly basis
- of use
- of incalculable worth
- open to modification
- of the same opinion
- overbright
- on top
- other team
- onlookers
- of prime importance
- on a grand scale
- oxidized
- over-priced
- oversupply
- overwinter
- overindulge oneself
- over here
- over the top
- overeach
- occur in rotation
- octad
- one and the same
- on an incline
- occurring every day
- outcasts
- obscuring
- oozing
- ovate
- on impulse
- one's bag
- out of contact with
- overplaying
- on the wing
- objections
- omposite
- over-trustful
- on one's side
- out-turn
- once again
- overbirm
- over-dramatic
- on the road to
- own up to
- open to bribery
- old-age pensioner
- owned
- overprotected
- overspread
- outward appearance
- operable
- odinarily
- over-reach
- open to argument
- out in the front
- overhanging
- older
- on special offer
- on the farther side of
- open the door to
- on the spur of the moment
- oxygenate
- offer suggestions
- opera star
- obtaining
- offer for sale
- outage
- open to the weather
- offer prayers
- overuse
- overhear
- on the agenda
- one way or another
- ooze out
- oilcan
- out of the corner of one's eye
- object of virtue
- on account
- open-mindedness
- outward form
- offer one's life
- overtly
- of sound mind
- opacity
- overdrink
- obtrude
- observer viewers audience
- on the side of
- odds-on
- overdraft
- old wives' tale
- of great consequence
- overindulgent
- of high standing