Cy, CY, or cy may refer to:
Cyprus (/ˈsaɪprəs/; Greek: Κύπρος IPA: [ˈcipros]; Turkish: Kıbrıs IPA: [ˈkɯbɾɯs]), officially the Republic of Cyprus (Greek: Κυπριακή Δημοκρατία; Turkish: Kıbrıs Cumhuriyeti), is an island country in the Eastern Mediterranean and the third largest and third most populous island in the Mediterranean.
Cystic fibrosis (CF) is a genetic disorder that affects mostly the lungs, but also the pancreas, liver, kidneys, and intestine.
Cybercrime, or computer related crime, is crime that involves a computer and a network. The computer may have been used in the commission of a crime, or it may be the target.
Cyrus II of Persia (Old Persian: 𐎤𐎢𐎽𐎢𐏁 Kūruš; New Persian: کوروش Kūrosh; Hebrew: כֹּרֶשׁ Koresh; c. 600 – 530 BC), commonly known as Cyrus the Great and also called Cyrus the Elder by the Greeks, was the founder of the Achaemenid Empire.
Cyclops (born: Scott Summers) is a fictional superhero appearing in American comic books published by Marvel Comics and is a founding member of the X-Men.
Cycling, also called bicycling or biking, is the use of bicycles for transport, recreation, exercise or sport.
CyanogenMod (/saɪ.ˈæn.oʊ.ˌdʒɛn.mɒd/; sigh-AH-no-GEN-mod) (CM) is a discontinued popular open-source operating system for smartphones and tablet computers, based on the Android mobile platform.
Cyberbullying or cyberharassment is a form of bullying or harassment using electronic forms of contact.
Cytochromes P450 (CYPs) are proteins of the superfamily containing heme as a cofactor and, therefore, are hemoproteins.