-íodh

• -igheadh (obsolete)
• -aíodh (broad form)

From -igh +‎ -adh.

(Past indicative autonomous)

• (Munster) IPA^(key): /iːɡ/
• (Galway) IPA^(key): /iːvˠ/
• (Mayo, Ulster) IPA^(key): /iːw/

(Elsewhere)

• (Munster) IPA^(key): /iːx/
• (Galway) IPA^(key): (before sé, sí, sibh, siad) /iːtʲ/, (elsewhere) /iːx/
• (Mayo, Ulster) IPA^(key): (before sé, sí, sibh, siad) /iːtʲ/, (elsewhere) /iːw/

-íodh

1. Analytic ending of second conjugation verbs in the habitual past tense and the past subjunctive mood
2. Autonomous ending of second conjugation verbs in the indicative past tense
3. Third person singular ending of second conjugation verbs in the imperative mood