What is the meaning of Scabby?

Affected with scabs; full of scabs.

Diseased with the scab (mange): mangy.

Having a blotched, uneven appearance.

Injured by the attachment of barnacles to the carapace of a shell.

Working against union policies, working to bust unions; in particular, being a scab (worker who crosses a union picket line).

Stingy.

Source: wiktionary.org