noun
Etymology: short for spermaceti whale
: a large toothed whale ( Physeter catodon syn. P. macrocephalus ) that has large conical teeth in the lower jaw only and no whalebone, attains a length of about 60 feet, has a large closed cavity in the head containing a fluid mixture of spermaceti and oil and a blubber yielding oil of superior quality, and produces ambergris as a pathological secretion of its intestines — called also black whale ; see pygmy sperm whale
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