crummy /ˈkɹʌmi/adjective 3noun 2forms 3 adjective3 •(informal) Bad; poor.Do not bother buying crummy knives if you are serious about cooking. •(old-fashioned) Full of crumb or crumbs. •(old-fashioned) Soft, like the crumb of bread; not crusty. noun2 •(US, informal) A small van, bus, or railway car used to transport loggers or other resource workers to and from the worksite. •A cow with a crumpled horn. formscrummies · crummier · crummiest