gleg /ɡlɛɡ/adjective 1noun 1verb 1forms 5 adjective1 •(Scotland) Smart; quick; brisk.One patted her neck, and assured her she was the gleggest and bonniest young thing she had ever seen. — 1856 noun1 •(Northern-England, no longer used) A look or glance.And besides, you'd do the tomb so well. Everybody feels as if they want a gleg at the skeleton in your vault. — 1913 verb1 •(Northern-England) To glance. formsglegged · glegging · glegs · glegger · gleggest