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(Greek orthography) A small iota written below an alpha, eta or omega – e.g. in ᾠδή – representing a vocalic offglide that was pronounced in early Ancient Greek, but later became silent; invented in the Middle Ages in order to mark those vowels which would originally have had such an offglide.

Iota subscripts in the word ᾠδῇ, ("ode", dative)

(Greek orthography) A small iota written below an alpha, eta or omega – e.g. in ᾠδή – representing a vocalic offglide that was pronounced in early Ancient Greek, but later became silent; invented in the Middle Ages in order to mark those vowels which would originally have had such an offglide.

Archaizing spelling with adscripts instead of subscripts. In pre-classical times, ancient Greek had long-vowel diphthongs, which evolved into monophthongs, mostly during the classical period and after. They continued to be written as diphthongs until the medieval period, when the iota subscript was introduced, reflecting the change in pronunciation.

(Greek orthography) A small iota written below an alpha, eta or omega – e.g. in ᾠδή – representing a vocalic offglide that was pronounced in early Ancient Greek, but later became silent; invented in the Middle Ages in order to mark those vowels which would originally have had such an offglide.

Greek treatment of both iota adscript and iota subscript: the word " ᾠδῇ ", "(to an) ode", dative case. Normal modern typesetting in capitalized word. Marked iota in the beginning is iota adscript and marked iota in the end is iota subscript.