The closest the Kojien comes to any notion of spiritual is in (3), with the mention of 心 kokoro, which has a wide range of meanings.
I see in some of the older stuff the use of kokoro
and I was not familiar with that term. The phrase later came up in "Budo Training in Aikido." It seems to be used as a general term that describes the unification of mind (intention) and body. Oddly enough, it seems the translation chooses to use this term in addition to spirituality (implying maybe some separation between ki
as "intent of the mind" and a spiritual connotation?). I enjoyed hearing more about that concept though; thank you Dr. Goldsbury.