cock on adjective 1exclamation 1verb 1forms 3 adjective1 •(UK, informal) Performed well; excellent; exact; correct.Chris has got it cock on, the only way to do it is by using a membraine. Rendering it both sides WILL NOT sort out the damp problem, no mater how much waterproofer you use. — 2010 exclamation1 •(UK, informal) Good work; well done; excellent.Cock-on mate well done! — 2010 verb1 •(slang, old-fashioned) To exaggerate; to overcharge. formscocked on · cocking on · cocks on