E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
A man cunning and selfish; one wise in his own interest; one who avoids talking at meals that he may enjoy his food the better. So called from the old proverb, The still sow eats the wash or draff.
We do not act that often jest and langh;
Tis old but true, Still swine eat all the draugh.