impalpable
adjective /ɪmˈpælpəbl/
/ɪmˈpælpəbl/
(formal)- that cannot be felt physically
触摸不到的;感觉不着的 - very difficult to understand
难以理解的;难懂的 opposite palpable
词源early 16th cent.: from French, or from late Latin impalpabilis, from in- ‘not’ + palpabilis, from Latin palpare ‘feel, touch gently’.