The origin of the word "spirit" was to breathe:
http://dictionary.reference.com/browse/spirit
Origin:
1200–50; ME (n.) < L
spīritus orig., a breathing, equiv. to
spīri-, comb. form repr.
spīrāre to breathe +
-tus suffix of v. action
Spir"it\, n. [OF. espirit, esperit, F. esprit, L. spiritus, from spirare to breathe, to blow. Cf.
Conspire,
Expire,
Esprit,
Sprite.]