disbelieving 0571 - apistos {ap'-is-tos}; from 0001 (as a negative particle) and 4103; (actively) {disbelieving}, i.e. without Christian faith (specially, a heathen); (passively) untrustworthy (person), or incredible (thing): -- that believeth not, faithless, incredible thing, infidel, unbeliever(-ing).
unbelieving 0544 - apeitheo {ap-i-theh'-o}; from 0545; to disbelieve (wilfully and perversely): -- not believe, disobedient, obey not, {unbelieving}.
unbelieving 0569 - apisteo {ap-is-teh'-o}; from 0571; to be {unbelieving}, i.e. (transitively) disbelieve, or (by implication) disobey: -- believe not.
unbelieving 0878 - aphron {af'-rone}; from 0001 (as a negative particle) and 5424; properly, mindless, i.e. stupid, (by implication) ignorant, (specially) egotistic, (practically) rash, or (morally) {unbelieving}: -- fool(-ish), unwise.