DDE may refer to: D.D.E. (band), a Norwegian rock band Delay differential equation, a type of differential equation Deep-dose equivalent, a measure of radiation absorbed by the body Dichlorodiphenyldichloroethylene, a chemical that results from the breakdown of DDT Doctrine of double effect, a set of ethical criteria to evaluate the permissibility of acting when one's otherwise legitimate act may also cause an effect one would normally be obliged to avoid Dwight D. Eisenhower, the 34th president of the United States Dynamic Data Exchange, a Microsoft Windows and OS/2 inter-application data communication protocol Escort destroyer, a US Navy classification used between 1945 and 1962 D.De., an abbreviation used for the United States District Court for the District of Delaware Deepin Desktop Environment, a Desktop Environment used by several Linux Distributions