Webster's 1828 Dictionary
UNTHOUGHTFUL
a.unthaut'ful. Thoughtless; heedless. Unthought of, not thought of; not regarded not heeded.
New American Oxford Dictionary
unthought
un thought |ˌənˈTHôt ənˈθɔt | ▶adjective 1 (unthought of ) not imagined or dreamed of: the old develop interests unthought of in earlier years. 2 not formed by the process of thinking.
Oxford Dictionary
unthought
un |thought |ʌnˈθɔːt | ▶adjective 1 (unthought of ) not imagined or dreamed of: the old develop interests unthought of in earlier years. 2 not formed by the process of thinking.
Oxford Thesaurus
unthought of
unthought of adjective what we have today was once unthought of and in most cases seemed impossible: unpredicted, unforeseen, unanticipated, unplanned, accidental, unlooked for, unsought, unexpected, not bargained for; sudden, abrupt, surprising, startling, astonishing, abnormal, out of the blue. ANTONYMS expected, predictable.
Sanseido Wisdom Dictionary
unthought-of
ù n th ó ught-of 形容詞 思いがけない, 意外な .