Argument: "A sequence of statements such that some of them (the premises) purport to give reason to accept another of them, the conclusion. Since we speak of bad arguments and weak arguments, the premises of an argument need not really support the conclusion, but they must give some appearance of doing so or the term ‘argument’ is misapplied. Logic is mainly concerned with the question of validity: whether if the premises are true we would have reason to accept the conclusion. A valid argument with true premises is called sound. A valid deductive argument is one such that if we accept the premises we are logically bound to accept the conclusion and if we reject the conclusion we are logically bound to reject one or more of the premises. Alternatively, the premises logically entail the conclusion. A good inductive argument -- some would reserve ‘valid’ for deductive arguments -- is one such that if we accept the premises we are logically bound to regard the conclusion as probable, and, in addition, as more probable than it would be if the premises should be false."
Audi, R. (Ed.). (1999). The Cambridge Dictionary of Philosophy (2nd ed.). New York, NY: Cambridge University Press