scepticEnglishOxford English Thesaurussceptic noun 1 sceptics said the marriage wouldn't last: cynic, doubter, questioner, scoffer; pessimist, prophet of doom; rare Pyrrhonist, minimifidian. 2 empowered by that Spirit, sceptics have found faith: agnostic; atheist, non-theist, unbeliever, non-believer, disbeliever, doubting Thomas; rationalist; rare nullifidian. ▷antonyms believer.sceptic Oxford Dictionary of English