half size

American  

noun

1. any size in women's garments designated by a fractional number from 12½ through 24½, designed for a short-waisted, full figure.

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half-size British  

noun

1. any size, esp in clothing, that is halfway between two sizes

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Example Sentences

Important note: The shoes run large, so order a half size down.

From Los Angeles Times

The half size portion includes a sizable amount of neck meat, which is a fully hands-on experience for anyone up for it, but there’s also plenty of boneless slabs for the taking.

From Seattle Times

You may need to go up a half size.

From Washington Post

“My right foot is a half size smaller than my left foot,” I say.

From Literature

The caps lock key is half size, the arrow keys are surrounded by home and end keys, and worst of all, the delete key is found right next to the backspace key, with no space between them.

From The Verge