(calculus) Initialism of delay differential equation. / (computing) Initialism of Dynamic Data Exchange. / (ethics) Initialism of doctrine of double effect.

(finance) A second-order measure of derivative price sensitivity, expressed as the instantaneous rate of change of delta with respect to time.

(finance) A second-order measure of derivative price sensitivity, expressed as the rate of change of vega with respect to changes in the spot price, or equivalently the rate of change of delta with respect to changes in the volatility of the underlying asset.