| Language | Reflex(es) | Gloss | Grammar | Sources |
|---|
| Celtic |
| Old Irish | en, in(i)- | in | prep | GED LRC |
| English |
| Old English | and, ond | and | conj | AHD LRC |
| Old English | beneoþan, benyðan | beneath | prep | W7 ASD LRC |
| Old English | binnan | within | prep | W7 LRC |
| Old English | in | in, into | prep | LRC |
| Old English | inn | into | prep | GED LRC |
| Old English | inna(n) | (from) within | adv | LRC |
| Old English | inne | inside, within | adv | GED LRC |
| Old English | innemest | inmost, innermost | adj | GED LRC |
| Old English | innera | inner | adj | GED LRC |
| Old English | innera | inner, interior | adj.comp | W7 LRC |
| Old English | neoþan | below, beneath | adv | W7 LRC |
| Old English | niþera, neoþera | nether | adj.comp | W7 ASD LRC |
| Old English | niþer(e) | down, below, beneath | adv | W7 ASD LRC |
| Old English | underneoþan | underneath | adv | W7 ASD LRC |
| Northumbrian | bi(o)nna | within | prep | ASD LRC |
| Middle English | and | and | conj | W7 LRC |
| Middle English | ben | within | adv | W7 LRC |
| Middle English | beneth(e), beneyth | beneath | adv | W7 MEV LRC |
| Middle English | dissenteris | dysentery | n | W7 LRC |
| Middle English | en- | en- | vb.pfx | W7 LRC |
| Middle English | entrailles | entrails | n | W7 LRC |
| Middle English | entren | to enter | vb | W7 LRC |
| Middle English | in | in, in- | adv | W7 LRC |
| Middle English | inn | inn | n | W7 LRC |
| Middle English | inner | inner | adj.comp | W7 LRC |
| Middle English | inter-, enter- | inter- | pfx | W7 LRC |
| Middle English | intro- | intro- | pfx | W7 LRC |
| Middle English | nether | nether | adj | W7 LRC |
| Middle English | undernethe | underneath | prep | W7 LRC |
| English | and | also | conj | AHD W7 LRC |
| English | atoll | coral island: lagoon inside reef | n | AHD W7 LRC |
| English | ben | within | adv | AHD W7 LRC |
| English | beneath | below, in/to lower position | adv | AHD W7 LRC |
| English | bilander | small 2-masted merchant vessel | n | AHD W7 LRC |
| English | dedans | open gallery at service end of tennis court | n | AHD W7 LRC |
| English | dysentery | severe infectious diarrhea with mucus/blood passage | n | AHD W7 LRC |
| English | em- | be/go/put (with)in/on (e.g. emplace) | vb.pfx | AHD W7 LRC |
| English | en- | be/go/put (with)in/on (e.g. enthrone) | vb.pfx | AHD W7 LRC |
| English | endo- | within | pfx | AHD LRC |
| English | endoergic | re: (nuclear) energy absorption | adj | AHD LRC |
| English | endothecium | inner lining of mature anther | n | AHD W7 LRC |
| English | enkephalin | endorphin with opiate qualities | n | AHD LRC |
| English | enter | to go/come in | vb | AHD W7 LRC |
| English | enteric | intestinal, re: enteron | adj | AHD W7 LRC |
| English | enteron | intestines, alimentary canal | n | AHD W7 LRC |
| English | ent(o)- | inner, inside, within | pfx | AHD W7 LRC |
| English | entrails | guts, viscera | n | AHD W7 LRC |
| English | entropy | measure of disorder in closed thermodynamic system | n | AHD W7 LRC |
| English | esoteric | designed for/understood by specially initiated | adj | AHD W7 LRC |
| English | esotropia | cross-eye syndrome | n | AHD LRC |
| English | exenterate | to remove contents of (e.g. pelvis) | vb.trans | AHD W7 LRC |
| English | in- | (with)in, into, toward | pfx | AHD W7 LRC |
| English | in | into, inside, within | prep | AHD W7 LRC |
| English | inn | public house for lodging/entertaining travelers | n | AHD W7 LRC |
| English | inner | situated farther in | adj.comp | AHD W7 LRC |
| English | inter- | between, among, amidst | pfx | AHD W7 LRC |
| English | interim | interval, time intervening | n | AHD W7 LRC |
| English | interior | inner, lying/occurring/functioning within limits | adj | AHD W7 LRC |
| English | interloper | meddler, intruder, encroacher | n | AHD W7 LRC |
| English | intern | internal | adj | AHD W7 LRC |
| English | internal | existing/situated within limits/surface | adj | AHD W7 LRC |
| English | intestine | internal | adj | AHD W7 LRC |
| English | intestine | tubular alimentary canal from stomach to anus | n | AHD W7 LRC |
| English | intima | innermost coat of organ | n | AHD W7 LRC |
| English | intimate | to declare, announce | vb.trans | AHD W7 LRC |
| English | intine | endosporium, innermost wall of spore/pollen grain | n | AHD LRC |
| English | intra- | within | pfx | AHD W7 LRC |
| English | intrados | interior curve of arch/vault | n | AHD W7 LRC |
| English | intro- | in, into | pfx | AHD W7 LRC |
| English | introgression | ingress, going in | n | AHD W2I LRC |
| English | introvert | to turn/draw inward | vb | AHD W7 LRC |
| English | intussusception | drawing in from without | n | AHD W7 LRC |
| English | inventory | itemized list | n | AHD W7 LRC |
| English | inverness | loose belted coat with cape | n | AHD W7 LRC |
| English | mesentery | vertebrate membrane: double fold of peritoneum | n | AHD W7 LRC |
| English | nether | lower, situated down/below | adj | AHD W7 LRC |
| English | sannyasi | Hindu ascetic mendicant | n | AHD W7 LRC |
| English | underneath | directly below, close beneath | prep | AHD W7 LRC |
| West Germanic |
| Old Frisian | binn(i)a | within | prep | ASD LRC |
| Old Frisian | in | in, into | prep | GED LRC |
| Old Frisian | in(n)a | inside | adv | GED ASD LRC |
| Old Frisian | inne | inside, within | adv | ASD LRC |
| Old Frisian | innere, inra | inner | adj | GED ASD LRC |
| Old Frisian | nither | down, below, beneath | adv | ASD LRC |
| Frisian | binnen | within | prep | ASD LRC |
| Dutch | billander | bilander | n | W7 LRC |
| Dutch | bin | inside | prep | W7 LRC |
| Dutch | binnen | within | prep | ASD LRC |
| Dutch | en | and | conj | TLL LRC |
| Old Saxon | in | in, into | prep | GED LRC |
| Old Saxon | inna(n) | inside, within | adv | GED LRC |
| Old Saxon | inne | inside, within | adv | ASD LRC |
| Old Saxon | niðar | down, below, beneath | adv | ASD LRC |
| Old High German | enti | and | conj | W7 LRC |
| Old High German | in | in, into | prep | GED LRC |
| Old High German | inna, inni, inne | inside, within | adv | ASD LRC |
| Old High German | in(n)ana, innan | inside, within | adv | GED ASD LRC |
| Old High German | innaro, innero | inner | adj | GED ASD LRC |
| Old High German | nidar | down | prep | W7 ASD LRC |
| Old High German | unt | unto, until | prep | W7 LRC |
| Old High German | untar | between, among | prep | W7 LRC |
| Middle High German | binnen | within | prep | ASD LRC |
| German | binnen | within | prep | ASD LRC |
| German | in | in, into | prep | LRC |
| German | innen | within | adv | ASD LRC |
| German | nieder | low, down, nether | adj | ASD LRC |
| German | und | and | conj | TLL LRC |
| North Germanic |
| Old Norse | inn | in, within | adv | LRC |
| Old Norse | innan | into, (from) within | prep | LRC |
| Old Norse | inni | inside, within | adv | LRC |
| Old Norse | inni | inn, dwelling | n | W7 LRC |
| Old Norse | í | in, within; among; during; into, onto | prep | LRC |
| Old Norse | neðan | underneath, from below/beneath | adv | LRC |
| Old Norse | niðr | down | adv | LRC |
| Old Norse | undorn | the time before or after the midday meal | n.masc | LRC |
| Old Icelandic | inni | inside | adv | GED LRC |
| Old Icelandic | inri | inner | adj | GED LRC |
| Old Icelandic | ī | in | prep | GED LRC |
| Old Icelandic | niðra, niðrað | to lower, put down | vb | ICE LRC |
| Icelandic | innan | (from) within | adv | ASD LRC |
| Icelandic | inni | indoors | adv | ASD LRC |
| Icelandic | inri, iðri | inner | adj | ASD LRC |
| Icelandic | í | in, into | prep | ASD LRC |
| Icelandic | niðr | down, below, beneath | adv | ASD LRC |
| Danish | i | in | prep | TLL LRC |
| Danish | nederdel | skirt | n | TLL LRC |
| Swedish | i | in | prep | TLL LRC |
| East Germanic |
| Gothic | in | in, to, towards; by, among | prep | LRC |
| Gothic | inn | into | prep | GED LRC |
| Gothic | inna(n), innana | within, inwardly | prep | GED ASD LRC |
| Gothic | innuma | inner | adj | GED LRC |
| Italic |
| Old Latin | en | in | prep | GED LRC |
| Old Latin | endo | in | adv | GED LRC |
| Old Latin | interus | inward, interior | adj | W7 LRC |
| Latin | dysenteria | dysentery | n.fem | W7 LRC |
| Latin | en- | in | pfx | W7 LRC |
| Latin | exentero, exenterare, exenteravi, exenteratus | to disembowel | vb | W7 LRC |
| Latin | in, in-, im- | in, into | prep | LRC |
| Latin | inter | between, among | prep | LRC |
| Latin | interaneum | intestine(s) | n.neut | W7 LRC |
| Latin | interaneus | interior | adj | W7 LRC |
| Latin | interim | meanwhile | adv | W7 LRC |
| Latin | interior | inside | adj | W7 LRC |
| Latin | internus | internal | adj | W7 LRC |
| Latin | interpretor, interpretāri, interpretātus | to interpret | vb.dep | LRC |
| Latin | intestinum | intestine(s) | n.neut | W7 LRC |
| Latin | intestinus | of the interior | adj | W7 LRC |
| Latin | intimus | most interior, secret | adj | W7 LRC |
| Latin | intrā | inside, within, during | adv | LRC |
| Latin | intro, intrāre | to enter | vb | W7 LRC |
| Latin | intrō | within, (to the) inside | adv | W7 LRC |
| Latin | intus | within | adv | W7 LRC |
| Late Latin | esotericus | of within, re: writings destined to be read within a school | adj | W7 LRC |
| Late Latin | intimo, intimāre, intimāvī, intimātus | to put in, announce | vb | W7 LRC |
| Medieval Latin | intralia | entrails | n.fem | W7 LRC |
| New Latin | end- | inside | pfx | W7 LRC |
| New Latin | mesenterium | membranes in abdominal cavity | n.neut | W7 LRC |
| Portuguese | em | in | prep | TLL LRC |
| Portuguese | entre | between, among | prep | TLL LRC |
| Spanish | en | in | prep | TLL LRC |
| Spanish | entre | between, among | prep | TLL LRC |
| Old French | en- | in | prep | W7 LRC |
| Old French | entrer | to enter | vb | W7 LRC |
| Middle French | en-, in- | in | pfx | W7 LRC |
| Middle French | entrailles | entrails | n.fem.pl | W7 LRC |
| Middle French | inter- | between | pfx | W7 LRC |
| Middle French | interior | interior | adj | W7 LRC |
| Middle French | interne | internal | adj | W7 LRC |
| Middle French | intestin | intestine | n.masc | W7 LRC |
| Middle French | intro- | inside | pfx | W7 LRC |
| Middle French | mesentere | mesentery, intestinal membrane | n.fem | W7 LRC |
| French | dans | in | prep | TLL LRC |
| French | dedans | inside | prep | W7 LRC |
| French | en | in | prep | TLL LRC |
| French | entre | between, among | prep | TLL LRC |
| French | intrados | interior curve of arch/vault | n.masc | W7 R1 LRC |
| Italian | in | in | prep | TLL LRC |
| Balto-Slavic |
| Old Prussian | en | in | prep | GED LRC |
| Lithuanian | į̃, iñ | in | prep | GED LRC |
| Latvian | iekš | in | adv | LRC |
| Old Church Slavonic | vъ | in, into | prep | LRC |
| Old Church Slavonic | n'iva | field, ground | n.fem | LRC |
| Old Church Slavonic | on- | in | pfx | GED LRC |
| Hellenic |
| Greek | dysenteria | dysentery | n.fem | W7 LRC |
| Greek | εἰς, ἐς | towards | prep | LRC |
| Greek | eisō | within | adv | W7 LRC |
| Greek | ἐν, ἔνι, ἐνί | in | prep | GED LRC |
| Greek | en- | in | pfx | W7 LRC |
| Greek | ἔνδον | within | adv | GED LRC |
| Greek | ἔνειμι | to be in, be possible | vb | LRC |
| Greek | enteron | intestine | n.neut | W7 LRC |
| Greek | exenterizein | to burst out | vb | W7 LRC |
| Greek | esō | within | adv | W7 LRC |
| Greek | esōterikos | of within, writings destined to be read within a school | adj | W7 LRC |
| Greek | esōterō | within | adv | W7 LRC |
| Anatolian |
| Hittite | anda(n) | in | adv | GED LRC |
| Armenian |
| Armenian | i | in | prep | GED LRC |
| Indo-Iranian |
| Sanskrit | antara- | interior | n | AHD LRC |
| Sanskrit | ántaras | inside | prep | GED LRC |
| Sanskrit | antár | between | prep | GED LRC |
| Sanskrit | ni- | one's own | pfx | GED LRC |
| Sanskrit | ni | down | prep | W7 LRC |
| Hindi | sannyāsī | Hindu ascetic mendicant | n | W7 LRC |
| Tocharian |
| Tocharian B | -ne | in | prep | GED LRC |
| Tocharian A | -an | in | prep | GED LRC |