also au·toch·tho·nal or au·toch·thon·ic
- Originating or formed in the place where found; indigenous: autochthonous rocks; an autochthonous people; autochthonous folk tales. See Synonyms at native.
- Ecology Native to or produced within a system: an autochthonous species; algae that provide an autochthonous source of nutrients in a lake.
- au·toch′thon·ism, au·toch′tho·ny
- (native to the place where found, buried in place): allochthonous
Literally, "native to the soil"; from autochthon +"Ž -ous.