1) To be so physically unattractive as to resemble someone whose face has been trampled and repeatedly stomped on by a horse.

2) To have a face that visually mirrors the excrement and mud slop found under and between a horse's/mule's hoof.
Jim: Wow, that Ariel is so under the hoof!

Me: Well, that's the main reason poor dude can't get a date.
by DirtiDimitri January 29, 2011
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