The definition of a cavern is a large cave.(noun)
An example of a cavern is Mammoth Cave in Kentucky.
See cavern in Webster's New World College Dictionary
Origin: ME & OFr caverne < L caverna < cavus: see cave
See cavern in American Heritage Dictionary 4
Origin: Middle English caverne
Origin: , from Old French
Origin: , from Latin caverna
Origin: , from cavus, hollow; see keuə- in Indo-European roots.
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