TIL why sperm whales are called sperm whales: Spermaceti is derived from Medieval Latin sperma ceti, meaning "whale sperm" (from Latin sperma meaning "semen" o

TIL why sperm whales are called sperm whales: Spermaceti is derived from Medieval Latin sperma ceti, meaning "whale sperm" (from Latin sperma meaning "semen" or "seed", and ceti, the genitive form of "whale"). The substance was initially believed to be whale semen, due to its appearance when fresh. The substance is also the origin of the name of the sperm whale.