New American Oxford Dictionary
ill-conceived
ill-con ceived |ˈɪl kənˈˌsivd | ▶adjective not carefully planned or considered: ill-conceived schemes.
Oxford Dictionary
ill-conceived
ill-conceived ▶adjective not carefully planned or considered: ill-conceived schemes.
American Oxford Thesaurus
ill-conceived
ill-conceived adjective the atrium's ill-conceived design has received much criticism: badly planned, badly thought out, hare-brained, ill-advised, ill-considered, ill-judged, misjudged, injudicious, imprudent, unwise, hasty, rash.