E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Slubber-Degullion.
A nasty, paltry fellow. A slub is a roll of wool drawn out and only slightly twisted; hence to slubber, to twist loosely, to do things by
halves, to perform a work carelessly. Degullion is compounded of the word gull, or the Cornish gullan, a simpleton.