Ies Definition

suffix
Used to form the plural forms of nouns endings in consonant-y.
Country, countries; party, parties.
Wiktionary
Used to form the third person singular of the indicative of verbs ending in consonant-y.
Party, parties; parry, parries.
Wiktionary
noun

(rare) Plural form of i, the name of the letter I.

Wiktionary