What's the difference between 'half a [noun]' and 'a half [noun]'? Are these structures used interchangeably? 'Half an hour'/'a half hour', 'half a mile'/'a half mile', etc. I'm used to use 'half' as a predeterminer (e.g. 'half an hour'). Can I forget about the second structure altogether?

  • I'm struggling to find an explanation for when we use the second version. I think it's when the measure of time or distance is an established fact. 'I had to wait half an hour for a bus' vs. 'When you reach X station you will have a half hour wait for your train to Y.' 'We walked about half a mile' vs. 'It's a half mile walk to the station.' You could probably get away without using it. Jun 25 '20 at 8:56

The difference is small, and you would rarely be wrong to use one in place of the other.

I would probably say a half-thing only if that is a common or natural unit. Many broadcast programs run for a half-hour; you might buy a half-liter of beer. But nobody sells or stores half-apples, so I would say half an apple.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .