blackneb
/blakˈnɛb/noun
1 English regional ( northern ) and Scottish. Any of various (chiefly black-billed) birds; especially the carrion crow, Corvus corone. Now historical.
2 Scottish depreciative. A blackleg, a strike-breaker; = blacknob. Now historical.
Origin
Early 19th century (in an earlier sense). From black + neb. The motivation for senses 1 and 3 is unclear; sense 3 could either (in spite of the apparent chronology) show an alteration of blacknob by association with sense 2, or could perhaps show an extended use of sense 2, the strike-breaker being compared to a carrion crow.