| iénai |  | go | i-[51] | ἰέναι (iénai), ἴμμεναι, ἰόν, ἰών (ímmenai, ión, iṓn) | anion, anionic, cation, cationic, ion, ionic, ionize, polyanion, polycation |
| iâsthai |  | heal | iatr-[52] | ἰᾶσθαι (iâsthai), ἰατρός (iatrós), ἰατρικός (iatrikós), ἰατρεύειν (iatreúein), ἰατρεία (iatreía), ἴασις, ἴαμα | iatrogenic, physiatry, podiatrist, podiatry, psychiatrist, psychiatry |
| ikhthús |  | fish | ichthy-[53] | ἰχθύς, ἰχθύος (ikhthús, ikhthúos) | ichthyology, Ichthyophaga, ichthyophobia, ichthyoplankton, ichthyosis |
| eíkosi |  | twenty | icos-[54] | ϝεικοσι, εἴκοσι (eíkosi), εἰκοσάς, εἰκοσάκις “twenty times” | hemi-icosahedron, icosagon, icosahedron |
| íkteros |  | jaundice | icter-[55] | ἴκτερος (íkteros), ἰκτερικός (ikterikós), ἰκτεριάω | icteric, icterogenic, icterohemorrhagic, icterohepatitis, icteroid, icterus |
| eîdein |  | shape, form, picture | id- (ϜΙΔ) | εἶδειν (eîdein), εἶδος (eîdos) | eidetic, eidolon, eidos, idol, idolater, idolatry, idyll, idyllic, idyllist, pareidolia |
| ideîn |  | idea, thought | ide-[56] | ἰδεῖν (ideîn), ἰδέα (idéa) | ideogram, ideologue, ideology |
| ídios |  | own, peculiarity | idi-[57] | ϝίδιος, ἴδιος (ídios), “private, personal, one's own” | idiolect, idiom, idiopathic, idiopathy, idiophone, idiosyncrasy, idiosyncratic, idiot, idiotic |
| ís |  | sinew | in-[58] | ἴς, ἰνός (ís, inós), ἰνίον (iníon) | inion, inotrope, inotropic |
| |  | I, i | iota- | iota | iotacism |
| wíswos |  | equal, same | is-, iso-[59] | ϝίσϝος (wíswos), ἴσος (ísos) | isogloss, isograph, isometric, isomorphic, isosceles, isotonic, isotropic |
| iskhíon |  | hip joint | ischi-[60] | ἰσχίον (iskhíon), ἰσχιαδικός (iskhiadikós) | ischiadic, ischium, sciatic, sciatica |
