nut-bar noun 3adjective 1forms 4 noun3 •A confection containing nuts and sweeteners formed in a bar shape.The dark eyes of the dog focused mainly on Bo’s nut bar, occasionally shifting his gaze from the candy bar to Bo, then back again. — 2013 •(informal) An insane person, a crazy person, a madwoman or madman.The nut-bar in Bed Three kept us all awake with his morose, nonsensical prophesies. And by “all of us” I mean myself, the gentleman in Bed Two, and the nut-bar as well, of course — 2007 •A bar or shaft with an aperture for a bolt or threaded rod to attach to or pass through.The bit-screw, passing through the nut-bar, is then turned back from the face of the coal or rock as far as is found necessary, and the bit secured to the same. — 1879 adjective1 •(informal) Crazy, mad. formsnut bars · nut-bars · more nut-bar · most nut-bar