Could not find Ἰσθμίοις in Logeion dictionaries.
Ἰσθμίοις
Proper-name noun: neuter dative plural of
Ἴσθμια
Ἰσθμίοις
Proper-name adjective: masculine dative plural, Proper-name adjective: neuter dative plural, Proper-name noun: masculine dative plural of
Ἴσθμιος
See Ἰσθμίοις in Morpho