Of, relating to, or extending throughout a system; affecting or reaching the whole of a system.

What does it mean if something is systemic?

: of, relating to, or common to a system: such as. a : affecting the body generally systemic diseases. b : supplying those parts of the body that receive blood through the aorta rather than through the pulmonary artery.

Is it systemwide or system wide?

-wide (suffix): Hyphenate suffix when base word is three or more syllables, such as university-wide but campuswide, systemwide, statewide.