origin n.

"person, animal, or plant that has been in a country or region from earliest times," 1858, mistaken singular of aborigines (1540s; aboriginal is considered the correct singular in English), from Latin aborigines "the first inhabitants," especially of Latium, hence "the first ancestors of the Romans;" possibly a tribal name, or from or made to conform to the Latin phrase ab origine, which means literally "from the beginning."

This is from ab "off, away from" (see ab-) + ablative of origo "a rise, commencement, beginning, source; descent, lineage, birth," from stem of oriri "arise, rise; be born, be descended, receive life" (see origin). Extended 1789 to natives of other countries which Europeans have colonized, especially "aboriginal inhabitant of Australia." Australian slang shortening Abo attested from 1922 (n.), 1906 (adj.).

1570s, "to miscarry in giving birth," from Latin abortus, past participle of aboriri "to miscarry, be aborted, fail, disappear, pass away," a compound word used in Latin for deaths, miscarriages, sunsets, etc., which according to OED is from ab, here as "amiss" (see ab-), + stem of oriri "appear, be born, arise," from PIE *heri- "to rise" (see origin). [Watkins, contra de Vaan, etc., derives the second element from a suffixed form of PIE root *er- (1) "move, set in motion."]

The English word is attested from 1610s as "to deliberately terminate" anything (intransitive), but especially a pregnancy in a human or animal. Intransitive use in aeronautics and space-flight is by 1946. Transitive meaning "to cause (a woman) to miscarry" is recorded by 1916; with the fetus or pregnancy as the object of the action, by 1966. Related: Aborted; aborting. The Latin verb for "produce an abortion" was abigo, literally "to drive away."