HMG 
abbreviation
(In the UK) Her or His Majesty’s Government.
- opportunity knocks
- opportunity shop
- opportunity state
- opposability
- opposable
- opposant
- oppose
- opposed
- opposedness
- opposer
- opposing
- opposingly
- opposite
- opposite field
- opposite-leaved
- oppositely
- oppositeness
- opposite number
- opposite prompt
- oppositifolious
- opposition
- oppositional
- oppositionality
- oppositionist
- oppositionless