Dy

DY, D. Y., Dy, or dy may refer to:

Science and technology

 * $dy$, Leibniz's notation for the differential of a variable y
 * Dysprosium (symbol Dy), a chemical element
 * 1,4-Dioxane, a solvent

Astronomy

 * DY Persei, a variable star in the Perseus constellation
 * DY Persei variable, a subclass of R Coronae Borealis variables
 * DY Eridani, a triple star system less than 16.5 light years away from Earth

Businesses

 * Norwegian Air Shuttle (IATA code: DY)
 * Alyemda (former IATA code: DY), a former Yemeni airline
 * DY, clothing brand of singer Daddy Yankee

People

 * Dy (surname), a surname in various cultures (including a list of people with the surname)
 * DY (rapper) (born 1984), Canadian rapper
 * DY, member of the American record production and songwriting team 808 Mafia
 * Lady Di, Diana, Princess of Wales

Places

 * DY, the official International vehicle registration code for Benin (formerly Dahomey)
 * DY postcode area, in England
 * DY Patil Stadium, a cricket stadium in India
 * D. Y. Patil college of Engineering and Technology, Kolhapur, in India

Other uses

 * dy (digraph), a digraph used in rendering the Xhosa and Shona languages, as well as some Australian Aboriginal languages such as Warlpiri
 * Deputy (disambiguation)
 * DY, a line of clothing from Puerto Rican singer Daddy Yankee