The linachos is found in some medieval encyclopedias. It has very sharp sight, and forces its chicks to look into the sun; any that cannot do so are rejected. It also attacks birds swimming in the water, forcing them under until they drown, then carries them away.

This story comes from the De animalibus historia by Aristotle (book 9, 33), but it had become confused by the time of the thirteenth century encyclopedias (Liber de natura rerum by Thomas of Cantimpré and its descendants). Thomas's account mixes parts related to the eagle (that rejects chicks that cannot look into the sun) and the osprey or sea eagle (that attacks other birds swimming on the water). Aristotle himself does not clearly distinguish between the eagle and the sea eagle, giving many of the same attributes to both. The bestiaries generally say it is the eagle that forces its chicks to look into the sun. Whether the name linachos is meant to refer to the eagle, the osprey, or both (or some other bird) is uncertain.