Main Entry: or·tho·gen·e·sis

Pronunciation: \ˌȯr-thə-ˈjen-ə-səs\

Function: noun

Inflected Form(s): plural or·tho·gen·e·ses \-ˌsēz\

: variation of organisms in successive generations that in some evolutionary theories takes place in some predestined direction and results in progressive evolutionary trends independent of external factors

—or·tho·ge·net·ic \-jə-ˈnet-ik\ adjective