wrong ‧ head ‧ ed /ˌrɒŋˈhedəd◂, ˌrɒŋˈhedɪd◂ $ ˌrɒːŋ-/ BrE AmE adjective
used to describe an idea, plan, or belief that someone has, that is based on wrong ideas that they are not willing to change
—wrongheadedly adverb
—wrongheadedness noun [uncountable]