Etymology
Advertisement
inter- 
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.
Related entries & more 
Advertisement
inter-war (adj.)

1939, in reference to the period between the world wars, from inter- + war (n.).

Related entries & more 
inter alia 
Latin, literally "amongst other things." from inter "among, between" (see inter-) + alia, neuter accusative plural of alius "(an)other" (see alias (adv.)). Latin for "among other persons" is inter alios.
Related entries & more 
Advertisement
intercommunion (n.)
1749, "intimate intercourse, fellowship," from inter- "between" + communion (n.).
Related entries & more 
interplay (n.)
1838, from inter- "between" + play (n.). "Reciprocal play," thus "free interaction."
Related entries & more