Monistic

[mon-iz-uh m, moh-niz-uh m] /ˈmɒn ɪz əm, ˈmoʊ nɪz əm/

noun
1.
Philosophy.

2.
the reduction of all processes, structures, concepts, etc., to a single governing principle; the theoretical explanation of everything in terms of one principle.
3.
the conception that there is one causal factor in history; the notion of a single element as primary determinant of behavior, social action, or institutional relations.
/ˈmɒnɪzəm/
noun
1.
(philosophy) the doctrine that the person consists of only a single substance, or that there is no crucial difference between mental and physical events or properties Compare dualism (sense 2) See also materialism (sense 2), idealism (sense 3)
2.
(philosophy) the doctrine that reality consists of an unchanging whole in which change is mere illusion Compare pluralism (sense 5)
3.
the epistemological theory that the object and datum of consciousness are identical
4.
the attempt to explain anything in terms of one principle only
n.

“the philosophical doctrine that there is only one principle,” 1862, from Modern Latin monismus, from Greek monos “alone” (see mono-). First used in German by German philosopher Baron Christian von Wolff (1679-1754).
monism [(moh-niz-uhm, mon-iz-uhm)]

A position in metaphysics that sees only one kind of principle whereas dualism sees two. On the question of whether people’s minds are distinct from their bodies, for example, a monist would hold either that mental conditions are essentially physical conditions (materialism), or that bodies depend on minds for their existence (idealism).