Before a number
We’ll pick you up around six.
In this country, we usually have dinner at about seven o’clock.
A:How long have you been living here?
B:For about three years.
Roughly 30 people are coming to my graduation party.
Up to 20 people are still missing after the earthquake.
She said she’d call here at or around ten o’clock.
We also use approximation in formal speech and writing:
The accident occurred at approximately 9 am.
In the region of 40 jobs are to be lost at the factory.
As many as 300 people were on the train when it broke down.
After a number
Number + -odd
Forty-odd people turned up at the demonstration. (at least 40 and maybe more)
A:How much oil does the tank hold?
B:I’m not sure. Fifty-odd litres, I’d say. (at least 50 litres and maybe more)
We do not use -odd to talk about time:
It’s about seven o’clock at least.
Not: …
seven-odd o’clock…
Number + head noun + or so
A:Can I have a lift to town with you?
B:Absolutely. I’ll be leaving in ten minutes or so.
Number + head noun + or something
A:What’s the weight limit for luggage?
B:20 kilos or something.
Number + head noun + or thereabouts (more formal)
[someone is giving directions]
Once you get to the school, turn left and our house is the first one on the left, half a mile, or thereabouts, up that road.
Number + more or less (informal speaking)
This is going to cost four hundred pounds, more or less. (preferred to This is going to cost more or less four hundred pounds.)
Using or between numbers
The bus from the airport usually costs just three or four pounds.
Adding the suffix -ish (informal speaking)
A:What time are we going out?
B:I think Linda said that she’d pick us up at sixish.
A:What age are Gabriela’s children?
B:Her daughter is fourish and her son must be at least seven.