- (in names of Spanish derivation) a contraction of de and the article el:Estanislao del Campo.
- (in names of Italian derivation) a contraction of di and the article il: Giovanni del Monte.
- a differential operator. Symbol: ∇
- delegate; delegation.
- delete; deletion.
- delineavit.
- Delaware.
- the differential operator i (∂/∂ x) + j (∂/∂ y) + k (∂/∂ z), where i, j, and k are unit vectors in the x, y, and z directions
- delegate
- Delaware
