pineal eye vs sense organ

pineal eye and sense organ both are nouns.

Word	Noun	Adjective	Verb	Adverb
pineal eye	Yes	No	No	No
sense organ	Yes	No	No	No

As nouns, sense organ is a hypernym of pineal eye; that is, sense organ is a word with a broader meaning than pineal eye:

pineal eye: a sensory structure capable of light reception located on the dorsal side of the diencephalon in various reptiles
sense organ: an organ having nerve endings (in the skin or viscera or eye or ear or nose or mouth) that respond to stimulation

Other hypernyms of pineal eye include receptor, sensory receptor.

pineal eye (noun)	sense organ (noun)
a sensory structure capable of light reception located on the dorsal side of the diencephalon in various reptiles	an organ having nerve endings (in the skin or viscera or eye or ear or nose or mouth) that respond to stimulation