sirenyoudaoicibaDictYouDict[siren 词源字典]
siren: [14] The Seirēnes were sea nymphs who, according to Greek mythology, sat on rocks luring impressionable sailors to their doom with the sweetness of their singing. Latin took the word over as sīrēna, and it passed into English via Old French sereine. The term was applied to an acoustical instrument invented in 1819 by Cagniard de la Tour, that produced musical sounds and was used for measuring the frequency of sound waves, and it was this that formed the basis of its later use (in the 1870s) for a device for giving loud warning signals.
[siren etymology, siren origin, 英语词源]
acoustic (adj.)youdaoicibaDictYouDict
c. 1600, from French acoustique, from Greek akoustikos "pertaining to hearing," from akoustos "heard, audible," verbal adjective from akouein "to hear," probably from copulative prefix a- (see a- (3)) + koein "to mark, perceive, hear," from PIE *kous- "to hear," which is perhaps from root *(s)keu- "to notice, observe" (see caveat). Acoustic guitar (as opposed to electric) attested by 1958. Related: Acoustical; acoustically.