autochthonous

UK: /ɔːˈtɒkθənəs/ US: (ô tok′thə nəs)

WordReference Random House Unabridged Dictionary of American English © 2025

au•toch•tho•nous  (ô tok′thə nəs), adj. 

1. Ecology, Anthropology pertaining to autochthons; aboriginal;
   indigenous (opposed to heterochthonous).
2. Pathology
   • found in the part of the body in which it originates, as a cancerous lesion.
   • found in a locality in which it originates, as an infectious disease.
3. Psychology of or pertaining to ideas that arise independently of the individual's own train of thought and seem instead to have some alien or external agency as their source.

[Geol.] (of rocks, minerals, etc.) formed in the region where found. Cf. allochthonous. Also, au•toch′tho•nal, au•toch•thon•ic  (ô′tok thon′ik). 

• autochthon + -ous 1795–1805

au•toch′tho•nism, au•toch′tho•ny, n. 
au•toch′tho•nous•ly, adv. 
au•toch′tho•nous•ness, n. 

Collins Concise English Dictionary © HarperCollins Publishers::

autochthonous / ɔːˈtɒkθənəs/, autochthonic / ˌɔːtɒkˈθɒnɪk/, autochthonal adjective

1. (of rocks, deposits, etc) found where they and their constituents were formed
2. inhabiting a place or region from earliest known times
3. (of some functions, such as heartbeat) originating within an organ rather than from external stimulation