cas|u|ist «KAZH u ihst», noun.
1. a person who reasons cleverly but falsely, especially in regard to right and wrong. SYNONYM(S): sophist, quibbler.
2. a person who decides questions of right and wrong in regard to conscience or conduct, applying general moral principles to a particular case: »
Who shall decide, when doctors disagree, and soundest casuists doubt, like you and me? (Alexander Pope).
Useful english dictionary. 2012.