Doubting Thomas is a biblical figure who refused to believe in the resurrection of Jesus until he saw it with his own eyes. The term has come to refer to someone who is skeptical or unwilling to accept something without proof. The crossword solutions for this term include 'DOUBTER' (7 letters), 'NONBELIEVER' (11 letters), 'SCEPTIC' (7 letters), 'CYNIC' (5 letters), 'AGNOSTIC' (8 letters), 'SEPTIC' (6 letters), and 'DISBELIEVER' (11 letters). All of these words refer to someone who is skeptical or unwilling to accept something without proof, and can be used interchangeably with the term 'Doubting Thomas'.