| Idiom | Meaning | Example | 
| off your high horse | 
(See get off your high horse)
 | 
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| off your rocker | 
crazy, not rational, around the bend
 | 
You gave away your piano? You're off your rocker!
 | 
| offer I couldn't refuse | 
(See an offer I couldn't refuse)
 | 
 | 
| offhand | 
casual, without much thought, off the cuff
 | 
I didn't think before I spoke. It was an offhand remark.
 | 
| offside (hockey) | 
going into the opponent's zone ahead of the puck
 | 
Wayne scored a beautiful goal, but Kurri was offside on the play.
 | 
| oh my gosh | 
oh no, oh dear, darn, rats
 | 
Oh my gosh! I've lost my keys!
 | 
| oilpatch | 
the local oil industry, the oil business
 | 
Calgary's oilpatch does not control the price of oil and gas.
 | 
| okay, OK | 
fine, good, cool
 | 
It's okay with me if your friends come to play.
 | 
| okay, OK | 
yes, alright
 | 
"Can I borrow your sweater?" "OK - if I can use your cell phone."
 | 
| Old Boys' Club | 
a group of wealthy old  men with political power
 | 
For City approval, talk to Craig. He's in the Old Boys' Club.
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