AY-dien (Irish Mythology) [key] submitted by Qarosignos, with the note: Correct Old Irish pronunciation (see Wikipedia article IPA: [eːdainʲ]) - medial -t- stands for /d/, and diphthong -ai- has not developed into modern Irish /i:/ (ao[i]) at this stage.
The current pronunciation AY-teen is incorrect regarding -t- and -ee-.