fal·la·cy 
/ˈfæləsi/ noun
plural fal·la·cies /ˈfæləsi/ noun 1 [count] : a wrong belief : a false or mistaken idea
▪ popular fallacies about medicine ▪ It's a fallacy (to believe) that the Earth is flat. 2 [noncount] : the quality of being false or wrong
▪ The fallacy of their ideas about medicine soon became apparent.
▪ popular fallacies about medicine ▪ It's a fallacy (to believe) that the Earth is flat.
▪ The fallacy of their ideas about medicine soon became apparent.
