Wiktionary
a. (context simile English) extremely white; totally white (of a color).
Usage examples of "white as driven snow".
And Bran stood aghast, for Gonar's face was white as driven snow and he shook with ague.
Two badgers came thundering out of the woods, one a female as old as the squirrel, but the other was a huge male, white as driven snow and whirling a big knotted oak club.
Snaresbrook kept reassuring herself that her conscience was as cool and white as driven snow.
The Patchouli Parlours might not be as white as driven snow but they were elegant places to work in and the girls, carefully chosen, weren't coerced into doing anything they didn't want to do.
All you have to do is get up in the witness box and swear that you never had any intention of marrying me, and you will be as white as driven snow.