WordNet sense 1 (not pertinent to the matter under consideration):

extraneous, impertinent, orthogonal

WordNet sense 2 (having no bearing on or connection with the subject at issue):

irrelevant

WordNet sense 3 ((often followed by `to') lacking importance; not mattering one way or the other):

indifferent

WordNet sense 4 (not important):

unimportant

WordNet sense 5 (lacking material body or form or substance):

spiritual

WordNet sense 6 (not having a material body):

disembodied, bodiless

WordNet sense 7 (without material form or substance):

incorporeal

WordNet sense 8 (lacking substance or reality; incapable of being touched or seen):

intangible

WordNet sense 9 (not consisting of matter):

nonmaterial