The tradition of Platonic and idealistic philosophy separates theory from practice in much the same way as it does mind from body, priveleging in both cases the "conceptual" (or moral) over the "material".
Praxis philosophies give primacy to a theory of action. The original expression is Aristotle's and refers to a symbolically meaningful activity, whose very doing, not its result, is the fulfillment of a cultural commitment. It can be defined as meaning rather than function.
Philosophers of Praxis include Hegel, Marx, and pragmatists such as William James.
Phenomenologically oriented theories of Praxis stress perception and embodiment.
For Lenin, the materialist dialectic requires constant verification through praxis to increase its cognitive content.
For the Frankfurt school in its earlier period, prior to 1937, truth was defined as "a moment of correct praxis." Subsequently, in the face of Fascism and Stalinism, the relation between theoretical truth and the political praxis of specific social groups began to appear increasingly remote. The "changing function of theory" signalled the growing gap between the critical truth of Marxism and the empirical consciousness of the proletariat, which theory continued to designate as the objective agent of the future transformation of society. (see Seyla Benhabib, "The Critique of Instrumental Reason", in Zizek, Mapping Ideology.)
Meaning can also be distinguished from value, when "The transformation of meaning into value deprives values of a referential anchoring in such a way that our only option is to view them as arbitrary products of our will." (Simpson, p.80)
see distinction that Hannah Arendt draws between action and work in The Human Condition.