sperm oil

noun Chemistry.
  1. a yellow, thin, water-insoluble liquid obtained from the sperm whale, used chiefly as a lubricant in light machinery, as watches, clocks, and scientific apparatus.

Origin of sperm oil

First recorded in 1820–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for sperm oil

sperm oil

noun
  1. an oil obtained from the head of the sperm whale, used as a lubricant
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