I. yu̇-ˈrē-kə interjection
Etymology: Greek heurēka I have found, from heuriskein to find; from the exclamation attributed to Archimedes on discovering a method for determining the purity of gold — more at heuristic
Date: 1603
— used to express triumph on a discovery
II. adjective
Date: 1948
: marked by usually sudden triumphant discovery
a eureka moment
III. yu̇-ˈrē-kä foreign term
Etymology: Greek
: I have found it — motto of California