drub

Short definition from Wiktionary

Noun

1. 1
   Carbonaceous shale; small coal; slate, dross, or rubbish in coal.

Verb

1. 1
   To beat (someone or something) with a stick.
2. 2
   To defeat someone soundly; to annihilate or crush.
3. 3
   To forcefully teach something.
4. 4
   To criticize harshly; to excoriate.