an outgrowth of the pineal gland that forms an eyelike structure on the top of the head in certain cold-blooded vertebrates
pineal eye in American English
noun
an eyelike structure that develops from the pineal apparatus in certain cold-blooded vertebrates
Also called: third eye
Word origin
[1885–90]This word is first recorded in the period 1885–90. Other words that entered Englishat around the same time include: lineup, reactor, retread, toner, zoom