D15 may refer to: Allis-Chalmers D15, an American tractor DA-15, an electrical connector Dewoitine D.15, a French fighter aircraft Dublin 15, a postal district in Ireland , a G- and H-class destroyer of the Royal Hellenic Navy , a Nairana-class escort carrier of the Royal Navy LNER Class D15, a British steam locomotive class LSWR D15 class, a British steam locomotive class Pennsylvania Railroad class D15, an American steam locomotive Slav Defense, a chess opening