- own goal
- on the stump
- odd parity
- on average
- off spring's
- on balance
- or otherwise
- on the beam
- oary
- on behalf of someone, on someone's behalf
- olive yard
- off the cuff
- occupational hazard
- overact
- of his ilk
- one who is not done his duties
- oil sardine
- on the part of done by
- occasional table
- out of luck
- ochlophobia
- off the hook
- overmanned
- ooze from
- only or on lie begetter
- occlussion
- opeidoscope
- oversleep
- offensively inquisitive query
- object computer
- omelette
- on cloud nine
- one too many
- on the market
- overcoming death
- ochery
- optimize
- of course
- overhead projector
- outstation
- off ramp
- odds and ends
- one who has controlled passions
- oracy
- optic centre
- opportunist
- outer garments
- odium
- on file
- otto of roses
- open secret
- observant
- orientalize
- omninescience
- obscurantism
- optical scanner
- ospitalisation
- out of doors
- opaqueness
- ontology
- octennial
- overindulgence
- olive
- over the moon
- old as the hills
- ocherous
- ovulation
- ordain
- oh for
- onam
- oppugnancy
- on the move
- overfly
- overarm
- on the face of it
- overreach oneself
- office-boy
- ordinary run of men
- over-enthusiasm
- obligatory
- ones cup of tea
- overwork
- overproduce
- obscenity
- opening door
- off-wind
- overshoot oneself
- observe
- old soldier
- occupation
- orphanize
- obsessive
- open face
- on the ropes
- ownership certificate
- obsolescent
- oological
- on the horizon
- odor
- one-mindedness