irregular
/i-ˈre-gyə-lər/
adjective
not being or acting in accord with laws, rules, or established custom
not conforming to the usual pattern of inflection; specifically : strong
not following a usual or prescribed procedure; especially, British : celebrated without either proclamation of the banns or publication of intention to marry
irregular conduct
irregular verbs
irregular anomalous unnatural mean not conforming to rule, law, or custom. irregular implies not conforming to a law or regulation imposed for the sake of uniformity in method, practice, or conduct. anomalous implies not conforming to what might be expected because of the class or type to which it belongs or the laws that govern its existence.
noun
one that is irregular: such as
a soldier who is not a member of a regular military force
merchandise that has minor defects or that falls next below the manufacturer's standard for firsts