having no justifying cause or reason; "a senseless, causeless murder"; "a causeless war that never had an aim"; "an apparently arbitrary and reasonless change"正当化する原因または理由のないさま謂れ無い
例:an apparently arbitrary and reasonless change 見たところ不確定で理由のない変化
not marked by the use of reason; "mindless violence"; "reasonless hostility"; "a senseless act"理論の使用によって示されない無意味