Passage: The term contains the character for negation, "not" or "without" (無), along with the character for heart-mind (心). The term is shortened from  mushin no shin (無心の心), a Zen expression meaning the mind without mind and is also referred to as the state of "no-mindness".  That is, a mind not fixed or occupied by thought or emotion and thus open to everything. It is translated by D.T. Suzuki as "being free from mind-attachment".

Question: What can no mindness really mean?
mind not fixed or occupied by thought or emotion and thus open to everything