A leading or drawing off of water from a stream or source. • The act of receiving anything from a source; the act of procuring an effect from a cause, means, or condition, as profits from capital, conclusions or opinions from evidence. • The act of tracing origin or descent; an instance thereof (for example, an etymology). • Forming a new word by changing the base of another word or by adding affixes to it. • The state or method of being derived; the relation of origin when established or asserted. • That from which a thing is derived. • That which is derived; a derivative; the result of a deduction. • The process of deriving one thing from another, especially in logic; a deduction. • A formal proof: a sequence of statements, each of which is logically entailed by those preceding (with respect to some collection of rules of inference), the initial statements being taken as axioms. • The process of application of the derivative operator to a function, yielding another function called the derived function of the first. • An algebraic generalization of the derivative operator (from its natural setting in the ring of real-valued functions) to a general associative algebra over a field. Formally, (given an algebra A over a field K) a K-linear endomorphism that satisfies Leibnitz's Law. • Any of several generalizations of this notion: a Hasse–Schmidt derivation, a graded derivation, etc. • A drawing of humors or fluids from one part of the body to another, to relieve or lessen a morbid process.