a : a system of law originating in the English chancery and comprising a settled and formal body of legal and procedural rules and doctrines that supplement, aid, or override common and statute law and are designed to protect rights and enforce duties fixed by substantive law
b : trial or remedial justice under or by the rules and doctrines of equity
c : a body of legal doctrines and rules developed to enlarge, supplement, or override a narrow rigid system of law