eurekayoudaoicibaDictYouDict[eureka 词源字典]
eureka: [16] The Greek mathematician Archimedes (c. 287–212 BC) was commissioned by King Hiero II of Syracuse to find out whether the goldsmith who had made a new crown for him had fraudulently mixed some silver in with the gold. In order to do so, Archimedes needed to ascertain the metal’s specific gravity. But how to do this? According to Plutarch, he decided to take a bath to ponder the problem.

He filled the bath too full, and some of the water overflowed – and it suddenly occurred to Archimedes that a pure-gold crown would displace more water if immersed than one made from an alloy. Elated at this piece of lateral thinking, Archimedes is said to have leapt out of the bath shouting heúrēka! ‘I have found!’, the perfect indicative of Greek heurískein ‘find’ (source of English heuristic [19]).

The earliest occurrence of the word in an English text as an exclamation of delight at discovery is in John Dee’s Preface, but there it appears in Greek characters; the first English author to fully naturalize it was probably Henry Fielding in Joseph Andrews 1742; ‘Adams returned overjoyed cring out “Eureka!”’ (The goldsmith, incidentally, had adulterated the gold.)
=> heuristic[eureka etymology, eureka origin, 英语词源]