undisciplined

adjective

1 the school said that his kid was lazy and undisciplined:

unruly, disorderly, disobedient, badly behaved, obstreperous, recalcitrant, refractory, intractable, wilful, wayward, delinquent, perverse, naughty, contrary, rebellious, mutinous, insubordinate, disruptive, attention-seeking, turbulent, errant, out of hand, out of control;

uncontrolled, uncontrollable, unrestrained, ungovernable, wild, capricious, unsteady, untrained, unschooled;

British, informal stroppy, bolshie;

archaic contumacious.

▷antonyms disciplined, well behaved.

2 nobody knew how undisciplined she had been with her money:

disorganized, unorganized, erratic, unsystematic, unmethodical, disorderly, chaotic, random, irregular, haphazard, in disarray, confused, muddled, jumbled;

lax, slapdash, slipshod, sloppy;

informal all over the place;

British, informal shambolic, all over the shop;

North American, informal all over the map, all over the lot.

▷antonyms orderly, organized.

undisciplined Oxford Dictionary of English