noun.
A woman who has an attractive body but less attractive facial features.
noun.
A person with mushy, unattractive facial features.
noun.
The face of an unattractive person.
Word Usage
"They have an uncanny eye for the smallest defect figure-wise, and can spot unwanted hair from fifty paces - but a sufficiently thin, waxed, tanned and silicon-enhanced 'butterface' will sail under their oh-so-picky radar as a 'drop dead babe.'"