Θησεῖα Save Θησεῖα, festival of Theseus Could not find Θησείων in Logeion dictionaries. Θησείων Proper-name noun: neuter genitive plural of Θησεῖα Θησείων Proper-name noun: neuter genitive plural of Θησεῖον See Θησείων in Morpho No dictionary entries for this word.