eureka

• POS: Interjection, Noun
• HYPHEN: eu=re=ka

CIDE DICTIONARY

eureka,  [Gr. I have found, perfect indicative of to find.].

 The exclamation attributed to Archimedes, who is said to have cried out “Eureka! eureka!” (I have found it! I have found it!), upon suddenly discovering a method of finding out how much the gold of King Hiero's crown had been alloyed. Hence, an expression of triumph concerning a discovery.  [1913 Webster]

OXFORD DICTIONARY

eureka, int. & n.
--int. I have found it! (announcing a discovery etc.).
--n. the exultant cry of 'eureka'.

Etymology

Gk heureka 1st pers. sing. perfect of heurisko find: attributed to Archimedes