-cy

suffix

(forms abstract nouns from adjectives)

Wiktionary

Pronunciation: /-si/ / /-sɪj/

suffix

Etymology: From Anglo-Norman -cie, ultimately from Latin -cia, -tia, Ancient Greek -κια (-kia), -τια (-tia), originally variants of Latin -ia and Ancient Greek -ια (-ia), -ία (-ía) or -εια (-eia). Original loan words like pharmacy and papacy could have formed the model.

Used to form nouns of state, condition or quality.
“private + -cy → privacy”
“frequent + -cy → frequency”
Used to form nouns of rank or office.
“president + -cy → presidency”
“abbot + -cy → abbacy”