- doubting, questioning, skeptical, sceptical - marked by or given to doubt; "a skeptical attitude"; "a skeptical listener"
Antonyms: trustful, trusting (indirect, via distrustful)
- disbelieving, skeptical, sceptical, unbelieving - denying or questioning the tenets of especially a religion; "a skeptical approach to the nature of miracles"
Antonym: credulous (indirect, via incredulous)