Cab
The cab is a small Hebrew dry measure. It surfaces in scripture only once, in a notice of how desperate the famine in besieged Samaria became.
A Famine Measure
During the Aramean siege of Samaria, prices ran wild as the food ran out. "And there was a great famine in Samaria: and, look, they besieged it, until a donkey's head was sold for 80 [shekels] of silver, and the fourth part of a kab of dove's dung for five [shekels] of silver" (2Ki 6:25). The cab — UPDV transliterates it as "kab" — is the small dry measure being quartered here, and even a quarter of one filled with dove's dung commanded a high price in silver. The verse is the only place the unit appears.