doubting thom·as \-ˈtäməs\noun Usage: usually capitalized T Etymology: after Thomas, one of Jesus' twelve apostles, who according to Jn 20:24-29 doubted Jesus' resurrection until he had proof of it : an incredulous or habitually doubtful person : doubter < even the doubting Thomases … were forced to admit the fertility of the black soil — R.H.Brown >