Online Etymology Dictionary

interrogatory (adj.): "containing or expressing a question," 1570s, from Late Latin interrogatorius "consisting of questions," from past participle stem of Latin interrogare "to ask, question, inquire; interrogate judicially, cross-examine," from inter- "between" (see inter-) + rogare "to ask, to question" (see rogation).
interrupt (v.): c. 1400, "to interfere with a legal right," from Latin interruptus, past participle of interrumpere "break apart, break off, break through," from inter- "between" (see inter-) + rumpere "to break" (see rupture (n.), and compare corrupt (adj.)). Meaning "to break into, break in upon, disturb the action of" (especially of speech) is from early 15c. in English (it is also in Latin). Related: Interrupted; interrupting.
interrupt (n.): "action of interrupting," 1956, originally in computing in reference to programs, from interrupt (v.).
interruption (n.): late 14c., "a break of continuity," from Latin interruptionem (nominative interruptio) "a breaking off, interruption, interval," noun of action from past participle stem of interrumpere "to break apart, break off" (see interrupt (v.)). Meaning "a breaking in upon some action" is from c. 1400; that of "a pause, a temporary cessation" is early 15c.
intersect (v.): 1610s (trans.), back-formation from intersection, or else from Latin intersectus, past participle of intersecare "intersect, cut asunder," from inter- "between" (see inter-) + secare "to cut" (see section (n.)). Intransitive sense is from 1847. Related: Intersected; intersecting.
intersect (n.): "point of intersection," 1850, from intersect (v.) or from Latin intersectum, neuter past pasticiple of intersecare. Earlier (1650s) it was used for "an insect."
intersection (n.): 1550s, "act or fact of crossing," from Middle French intersection (14c.) and directly from Latin intersectionem (nominative intersectio) "a cutting asunder, intersection," noun of action from past participle stem of intersecare "intersect, cut asunder," from inter- "between" (see inter-) + secare "to cut" (see section (n.)). In English originally a term in geometry; meaning "crossroads, a place of crossing" is from 1864. Related: Intersectional.
intersex (n.): "one having characteristics of both sexes," 1917, from German intersexe (1915); see inter- "between" + sex (n.). Coined by German-born U.S. geneticist Richard Benedict Goldschmidt (1878-1958). Intersexual is from 1866 as "existing between the sexes, pertaining to both sexes;" from 1916 as "having both male and female characteristics." Related: intersexuality.
interspace (n.): "space between" (any two things), early 15c., from Late Latin interspatium, from inter "between" (see inter-) + spatium (see space (n.)). As a verb, "fill or occupy the space between," 1832. Related: Interspaced; interspacing.
interspecific (adj.): "existing between species," 1889, from inter- "between" + specific, used here as an adjective to go with species.
intersperse (v.): 1560s, from Latin interspersus "strewn, scattered, sprinkled upon," past participle of *interspergere, from inter- "between" (see inter-) + spargere "to scatter" (see sparse). Related: Interspersed; interspersing.
interspersion (n.): 1650s, noun of action from intersperse.
interstate (adj.): 1838, American English, in reference to traffic in slaves, from inter- "between" + state (n.) in the U.S. sense. Interstate commerce is that carried on by persons in one U.S. state with persons in another. Noun sense of "an interstate highway" is attested by 1975, American English.
interstellar (adj.): 1620s, "situated between or among the stars," in reference to the night sky (modern astronomical sense is from 1670s), from inter- "between" + Latin stella "star" (see stellar). Intersiderial in the same sense is from 1650s.
interstice (n.): early 15c., from Old French interstice (14c.) and directly from Latin interstitium "interval," literally "space between," from inter- "between" (see inter-) + stem of stare "to stand," from PIE root *stā- "to stand, set down, make or be firm" (see stet). Related: Interstices.
interstitial (adj.): "pertaining to or situated in an interstice," 1640s, from Latin interstitium "interval" (see interstice) + -al (1). Related: Interstitially.
intersubjective (adj.): "existing between conscious minds" [OED], 1883, from German intersubjective (1881); see inter- "between" + subjective (adj.).
interterritorial (adj.): also inter-territorial, 1827, from inter- "between" + territory + -al (1).
intertextuality (n.): by 1974 in literary criticism, from inter- "between" + textual + -ity. Related: Intertextual (1879).
intertidal (adj.): also inter-tidal, "between the high and low water marks," 1853, from inter- + tidal (adj.).
intertribal (adj.): also inter-tribal, 1850; see inter- "between" + tribe (n.) + -al (1).
interturb (v.): "to disturb by interruption" (obsolete), 1550s, from Latin inturbus, past participle of inturbare "disturb by interruption," from in- "in" (see in- (2)) + turbare "to disturb, confuse" (see turbid). Related: Interturber (1530s).
intertwine (v.): 1640s (trans.), a hybrid from inter- + twine (v.). Intransitive sense is from 1782. Related: Intertwined; intertwining.
interurban (adj.): 1883, from inter- "between" + Latin urbs "city" (see urban (adj.)).
interval (n.): early 14c., "time elapsed between two actions or events," from Old French intervalle "interval, interim" (14c.), earlier entreval (13c.) and directly from Late Latin intervallum "a space between, an interval of time, a distance," originally "space between palisades or ramparts" [OED], from inter "between" (see inter-) + vallum "rampart, palisade, wall," which is apparently a collective form of vallus "stake," from PIE *walso- "a post" (see wall (n.)).

Metaphoric sense of "gap in time" also was in Latin. From c. 1400 in English as "a pause, an interruption in a state or activity." Musical sense "difference in pitch between two tones" is from c. 1600. Related: Intervallic.
intervene (v.): 1580s, "intercept" (obsolete), a back-formation from intervention, or else from Latin intervenire "to come between, intervene; interrupt; stand in the way, oppose, hinder," from inter "between" (see inter-) + venire "to come" (see venue). Sense of "come between, fall or happen between" (of events) is from c. 1600; that of "interfere, interpose oneself between, act mediatorially" is from 1640s. Related: Intervened; intervener; intervening.
intervenient (adj.): c. 1600, from Latin intervenientem (nominative interveniens), present participle of intervenire "to come between, interrupt," from inter- "between" (see inter-) + venire "come" (see venue). Related: Interveniently.
intervent (v.): "to come between" (obsolete), 1590s, from Latin interventus, past participle of intervenire "to come between, interrupt," from inter- "between" (see inter-) + venire "come" (see venue). Related: Intervented; interventing.
intervention (n.): early 15c., "intercession, intercessory prayer," from Middle French intervention or directly from Late Latin interventionem (nominative interventio) "an interposing, a giving security," literally "a coming between," noun of action from past participle stem of Latin intervenire "to come between, interrupt," from inter- "between" (see inter-) + venire "come" (see venue). Later "act of intervening" in any way; in 19c.-20c. often of international relations; by 1983 of interpersonal intrusions by friends or family meant to reform a life felt to be going wrong.
interventionism (n.): 1852, from intervention + -ism. Interventionist, as a noun, is recorded from 1846, originally in the international sense.
interview (n.): 1510s, "face-to-face meeting, formal conference," from Middle French entrevue, verbal noun from s'entrevoir "to see each other, visit each other briefly, have a glimpse of," from entre- "between" (see inter-) + Old French voir "to see" (from Latin videre; see vision). Modern French interview is from English. Journalistic sense "conversation with someone to obtain statements for publication" is from 1869 in American English.
The 'interview,' as at present managed, is generally the joint product of some humbug of a hack politician and another humbug of a newspaper reporter. ["The Nation," Jan. 28, 1869]
Meaning "personal meeting to discuss hiring or employment" is by 1921; earlier it was used in military recruiting (1918).
interview (v.): in early use also enterview, enterveu, 1540s, "to have a personal meeting," from interview (n.). Meaning "have an interview with" (usually with intent to publish what is said" is from 1869. Related: Interviewed; interviewing.
interviewee (n.): 1883, from interview (v.) + -ee.
interviewer (n.): 1868, in the journalistic sense, agent noun from interview (v.).
intervocalic (adj.): "between vowels," 1881, from inter- "between" + Latin vocalis "a vowel" (see vowel) + -ic.
interweave (v.): 1570s (trans.), hybrid from inter- + weave (v.). Intransitive sense from 1827. Related: Interweaving; interweaved; interwove; interwoven.
interwork (v.): c. 1600, a hybrid from inter- "between" + work (v.). Related: interworking. Past tense can be either interworked or interwrought.
interwoven (adj.): 1640s, past participle of interweave (q.v.).
intestacy (n.): "condition of dying without leaving a valid will," 1740, from intestate + -acy.
intestate (adj.): late 14c., from Old French intestat (13c.) and directly from Latin intestatus "having made no will," from in- "not" (see in- (1)) + testatus, past participle of testari "make a will, bear witness" (see testament). As a noun, "one who has not made out a will," from 1650s.
intestinal (adj.): early 15c., from medical Latin intestinalis, from Latin intestinum "an intestine, gut" (see intestine).
intestine (n.): "lower part of the alimentary canal," early 15c., from Middle French intestin (14c.) or directly from Latin intestinum "a gut," in plural (intestina), "intestines, bowels," noun use of neuter of adjective intestinus "inward, internal," from intus "within, on the inside," from PIE *entos, suffixed form of root *en "in" (see in).

Distinction of large and small intestines in Middle English was made under the terms gross and subtle. Intestine also was used as an adjective in English 16c.-19c. with a sense (as in French) of "internal, domestic, civil."
intestines (n.): "bowels," 1590s, from intestine, based on Latin intestina, neuter plural of intestinus (adj.) "internal, inward, intestine," from intus "within, on the inside," from PIE *entos, suffixed form of root *en "in" (see in (adv.)). Compare Sanskrit antastyam, Greek entosthia "bowels." The Old English word was hropp, literally "rope."
intice (v.): obsolete spelling of entice. Related: Inticed; inticing.
Intifada (n.): "Palestinian revolt," 1985, from Arabic, literally "a jumping up" (in reaction to something), from the verb intafada "to be shaken, shake oneself."
intimacy (n.): 1640s, from intimate (adj.) + -cy. Sense of "sexual intercourse" attested from 1670s but modern use is from newspaper euphemistic use (1882).
intimate (adj.): 1630s, "closely acquainted, very familiar," also "inmost, intrinsic," from Late Latin intimatus, past participle of intimare "make known, announce, impress," from Latin intimus "inmost, innermost, deepest" (adj.), also used figuratively, of affections, feelings, as a noun, "close friend;" superlative of in "in" (see in- (2)). Intimate (adj.) used euphemistically in reference to women's underwear from 1904. Related: Intimately.
intimate (v.): 1530s, "make known formally;" 1580s, "suggest indirectly," back-formation from intimation (which could explain the pronunciation) or else from Late Latin intimatus, past participle of intimare "to make known." The Old French verb was intimer. Related: Intimated; intimating.
intimate (n.): 1650s, "familiar friend, person with whom one is intimate," from intimate (adj.). Sometimes 17c.-19c. in false Spanish form intimado. Latin intimus had a similar noun sense. Intimates as a commercial euphemism for "women's underwear" is from 1988.
intimation (n.): mid-15c., "action of making known," from Middle French intimation (14c.), from Late Latin intimationem (nominative intimatio) "an announcement," noun of action from past participle stem of Latin intimare "make known, announce, impress" (see intimate (adj.)). Meaning "action of expressing by suggestion or hint, indirect imparting of information" is from 1530s.