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A particle of calcium carbonate found in the inner ear of vertebrates and involved in sensory perception.
Word Entries at Get Words: “otolith
otolith (literally, "ear stone")
The earbone of a fish.

The age of a fish is commonly estimated by counting the rings laid down annually in the otolith, much as the age of a tree is determined by counting the rings across its trunk.

This entry is located in the following unit: Ocean and Deep Sea Terms (page 4)