Origin and history of intercontinental

1818 as a purely geographical term, "relating to or of the nature of a continent," from continent (n.) + -al (1). In reference to the European mainland (as opposed to Great Britain), recorded from 1760.

Continental breakfast (the kind eaten on the continent as opposed to the kind eaten in Britain) is attested by 1855. As "pertaining to the government and affairs of the 13 revolutionary British American colonies," from 1774; the Continental Congress was so called from 1775.

Continental divide "line across a continent such that the drainage on one side feeds into one ocean or sea and that on the other feeds into a different body of water," was in use by 1865; continental slope "slope between the outer edge of the continental shelf and the ocean floor" is from 1849. Continental shelf "area of shallow sea around a continent, geologically part of the continent" is attested from 1888.

Continental drift "gradual movement of the continents across the earth's surface through geological time" (1925) is a translation of German Kontinentalverschiebung, proposed 1912 by German scientist Alfred Wegener (1880-1930); the theory was not widely accepted until after c. 1950.

word-forming element used freely in English, "between, among, during," from Latin inter (prep., adv.) "among, between, betwixt, in the midst of" (also used extensively as a prefix), from PIE *enter "between, among" (source also of Sanskrit antar, Old Persian antar "among, between," Greek entera (plural) "intestines," Old Irish eter, Old Welsh ithr "among, between," Gothic undar, Old English under "under"), a comparative of root *en "in."

A living prefix in English from 15c. and used with Germanic as well as Latinate words. Spelled entre- in French; most words borrowed into English in that form were re-spelled 16c. to conform with Latin except entertain, enterprise. In Latin, spelling shifted to intel- before -l-, hence intelligence, etc.