also inter-relate, 1831 (implied in interrelated), transitive, "bring into reciprocal relation," from inter- "between" + relate (v.). Intransitive sense "come into reciprocal relation" is attested from 1912. Related: Interrelating.
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.
1520s, "to recount, tell," from French relater "refer, report" (14c.) and directly from Latin relatus, used as past participle of referre "bring back, bear back" (see refer), from re- "back, again" + lātus "borne, carried" (see oblate (n.)).
The meaning "stand in some relation; have reference or respect" is from 1640s; transitive sense of "bring (something) into relation with (something else)" is from 1690s. Meaning "to establish a relation between" is from 1771. Sense of "to feel connected or sympathetic to" is attested from 1950, originally in psychology jargon. Related: Related; relating.
<a href="https://www.etymonline.com/word/interrelate">Etymology of interrelate by etymonline</a>
Harper, D. (n.d.). Etymology of interrelate. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/interrelate