noun
1. : a body of law derived from nature and binding upon human society in the absence of or in addition to institutional law: as
a. : the principles of justice discernible (as by the Stoics) by right reason
b. : jus gentium
c. : the part of divine law discernible (as by the Scholastics) to reason but not directly revealed
d. : a set of principles derived from an analysis of human societies and based (as by 18th century rationalists) principally upon certain natural rights having prior validity to institutional law
e. : the body of rules or customs derived from the general development of mankind and essential to the maintenance of human society
2. : a specific principle belonging to the total body of natural law
3. : law of nature