adjectives
having no personal preference
"impersonal criticism"; "a neutral observer"
having only a limited ability to react chemically; chemically inactive
"inert matter"; "an indifferent chemical in a reaction"
not supporting or favoring either side in a war, dispute, or contest
is similar to
not affiliated with any faction, party, or cause
possessing no distinctive quality or characteristics
is similar to
made neutral in some respect; deprived of distinctive characteristics
is similar to
not having or expressing opinions or views
having no hue
"neutral colors like black or white"
lacking distinguishing quality or characteristics
"a neutral personality that made no impression whatever"
is similar to
lacking in variety and interest
"a colorless and unimaginative person"; "a colorless description of the parade"
having no net electric charge