A correspondent writes to ask if he is allowed to say I've spent the past hour or so in the hall to mean 'less than an hour'. He thinks he uses or so to mean 'roughly', and this allows a meaning of less as well as more. His friend disagrees. What do I think?
The OED definition suggests it could be either: 'or about that amount or number; or thereabout' (so, sense 33b); but the examples tell a different story. The first recorded usages are from Shakespeare, as follows:
If I could go to hell for an eternal moment or so (The Merry Wives of Windsor, 2.1.50)
Some two thousand strong, or so (Twelfth Night 3.2.59)
The first couldn't conceivably mean 'less than a moment': or so here means 'one or a bit more'. The second is an estimate by Sir Toby Belch of how much money he has had from Sir Andrew Aguecheek. If the money was counted up and found to be only £1990, nobody would accuse Belch of being a liar. It is a vague estimate only. Here, or so means 'more or less'.
This suggests a working principle: the force of the phrase depends on the quantity involved. With small numbers (and especially when the number is just one) the sense is driven upwards. I could not possibly use an hour or so to mean less than an hour. This upwards direction I think is always present, but its force diminishes as the numbers increase. So, I could say 1500 or so people read her blog, suggesting that it is more, but allowing (if challenged) that the figure could be less.
There may also be an effect from the noun that is being quantified. Time-scales are determinate, so an hour or so allows little flexibility. But I think there was an audience of 20 or so at the theatre allows the possibility that there were 19 (or so) because audiences are unpredictable.
I'd be interested to know if anyone has a different intuition about this.