RhymeZone: karst definitions

Definitions of Karst:

name: A surname (common: 1 in 100000 families; popularity rank in the U.S.: #15167)

noun: (geology) A type of land formation, usually with many caves formed through the dissolving of limestone by underground drainage.
noun: A mountainous region in northeastern Italy and southwestern Slovenia.

(Definitions from Wiktionary)