madcap
adjective
noun
she was a boisterous madcap:
eccentric, crank, madman/madwoman, maniac, lunatic, psychotic;
oddity, odd fellow, character, individual;
hothead, daredevil;
informal crackpot, oddball, weirdo, loony, nut, nutcase, nutjob, cuckoo;
British, informal nutter;
North American, informal screwball;
US, informal wackadoo, wackadoodle;
Scottish, informal radge;
Australian, New Zealand, informal dingbat.
madcap Oxford Dictionary of English