spermaceti organ

zoology

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July 14, 2026

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The term "spermaceti organ" refers to a unique organ found in the head of sperm whales and, to a lesser extent, bottlenose whales. This organ contains a white, liquid wax that whalers historically mistook for whale sperm, leading to the whale's name and the substance's designation as "spermaceti".12

The spermaceti organ can be quite large, holding up to 2,000 liters of fluid and extending through 40% of the whale's body length. When extracted and chilled, this fluid solidifies into a waxy substance. Spermaceti was historically valued for its use in ointments, cosmetics, fine candles, and industrial lubricants. Chemically, it is primarily composed of esters of fatty acids and fatty alcohols.21

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sperm oil
… from the head cavity (spermaceti organ) and blubber of the sperm whale. Formerly used as a superior lighting oil and later as a lubricant, it was little used in the modern period apart from in certain toiletries and pharmaceuticals, although in 1950 advances in oil chemistry allowed it to…
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… from the head cavity (spermaceti organ) and blubber of the sperm whale. Formerly used as a superior lighting oil and later as a lubricant, it was little used in the modern period apart from in certain toiletries and pharmaceuticals, although in 1950 advances in oil chemistry allowed it to…
Read More

sperm whale
…upper lip where the fluid-filled spermaceti organ (which whalers called the case) is located; sperm oil and spermaceti were extracted from this fluid for lighting and lubrication. The spermaceti organ is unique to sperm whales. It has a volume as large as 2,000 litres (530 gallons) and can extend through…
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…upper lip where the fluid-filled spermaceti organ (which whalers called the case) is located; sperm oil and spermaceti were extracted from this fluid for lighting and lubrication. The spermaceti organ is unique to sperm whales. It has a volume as large as 2,000 litres (530 gallons) and can extend through…
Read More

cetacean
Sound production and communication
…it is occupied by the spermaceti organ and a fatty (adipose) cushion, both of which somehow function in the emission of sound for echolocation and were known by whalers as the “case” and the “junk,” respectively. The junk of the sperm whale is the fatty structure found in the forehead…
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…it is occupied by the spermaceti organ and a fatty (adipose) cushion, both of which somehow function in the emission of sound for echolocation and were known by whalers as the “case” and the “junk,” respectively. The junk of the sperm whale is the fatty structure found in the forehead…
Read More