Iodhadh
| Ogham letters ᚛ᚑᚌᚐᚋᚁᚂᚃᚓᚇᚐᚅ᚜ | |||||
| Aicme Beithe ᚛ᚐᚔᚉᚋᚓᚁᚂᚃᚄᚅ᚜ |
Aicme Muine ᚛ᚐᚔᚉᚋᚓᚋᚌᚍᚎᚏ᚜ | ||||
| ᚁ | [b] | Beith | ᚋ | [m] | Muin |
| ᚂ | [l] | Luis | ᚌ | [ɡ] | Gort |
| ᚃ | [w] | Fearn | ᚍ | [ɡʷ] | nGéadal |
| ᚄ | [s] | Sail | ᚎ | [st], [ts], [sw] | Straif |
| ᚅ | [n] | Nion | ᚏ | [r] | Ruis |
| Aicme hÚatha ᚛ᚐᚔᚉᚋᚓᚆᚇᚈᚉᚊ᚜ |
Aicme Ailme ᚛ᚐᚔᚉᚋᚓᚐᚑᚒᚓᚔ᚜ | ||||
| ᚆ | [j] | Uath | ᚐ | [a] | Ailm |
| ᚇ | [d] | Dair | ᚑ | [o] | Onn |
| ᚈ | [t] | Tinne | ᚒ | [u] | Úr |
| ᚉ | [k] | Coll | ᚓ | [e] | Eadhadh |
| ᚊ | [kʷ] | Ceirt | ᚔ | [i] | Iodhadh |
| Forfeda ᚛ᚃᚑᚏᚃᚓᚇᚐ᚜ | |||||
| ᚕ | [ea], [k], [x], [eo] | Éabhadh | |||
| ᚖ | [oi] | Ór | |||
| ᚗ | [ui] | Uilleann | |||
| ᚘ | [ia] | Ifín | |||
| ᚙ | [x], [ai] | Eamhancholl | |||
| ᚚ | [p] | Peith | |||
Iodhadh is the Irish name of the twentieth letter of the Ogham alphabet, ᚔ. In Old Irish, the letter name was idad. Its phonetic value is [i]. The original meaning of the letter name is uncertain, but it is likely an artificially altered pair with edad, much like Gothic pairþra, qairþra, and may refer to "yew".