isopiptesis

Etymology

Refashioning of the earlier spelling isepiptesis, from German Isepiptesen used by Alexander von Middendorff in his 1855 work Die Isepiptesen Russlands, from iso- + Ancient Greek ἐπίπτησις (epíptēsis, “flying down upon”), from ἐπι- (epi-, “upon”) + πτῆσῐς (ptêsĭs, “flight”), from πέτομαι (pétomai, “fly”).

isopiptesis means an isoline that joins points on a map where the individuals of a particular migratory species arrive at the same time each year. Lexicurio rates it Rare gem — a strength score of 82 out of 100.

noun

An isoline that joins points on a map where the individuals of a particular migratory species arrive at the same time each year.“The conclusion that the migration takes place at right angles to the isopipteses seemed justified; but, with regard to the direction of the bird's migration to be ascertained, could not possibly prove more exact than the premises themselves, the methods of inquiry, and the material.”