'''エーコー'''(古典ギリシア語:Ἠχώ、Echo)は、ギリシア神話に登場する森のニンフである。一般的には'''エコー'''と表記される。ギリシア語で元々[[木霊]]の意味で、その擬人化である。[[パーン (ギリシア神話)|パーン神]]と美青年[[ナルキッソス]]との恋で有名であるが、古典時代にはこのような話はなく、'''ヘレニズム時代以降の後世の物語'''である。エコーは文字通り[[木霊]]・反響などを意味する。
ギリシア神話において、エーコー(ˈɛkoʊ; ギリシャ語:Ἠχώ (Ē), 「響き」<ref>[https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dh%29xw%2F ἠχώ], Henry Liddell, Robert Scott, ''A Greek-English Lexicon'', on Perseus</ref>)は、シタエロン山(キサイロナス)に住んでいたオレイアス<ref>山と岩屋のニュンペーである。</ref>である。である<ref>Aristophanes, Translated by [[Eugene O'Neill Jr.]] (1938). ''Thesmophoriazusae''. Lines 990-1000. Available at [https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0042%3Acard%3D990 perseus.tufts.edu]</ref>。
In [[Greek mythology]], '''Echo''' ({{IPAc-en|ˈ|ɛ|k|oʊ}}; {{lang-el|Ἠχώ}}, ''Ēkhō'', "[[echo]]", from ἦχος (''ēchos''), "sound"<ref>[https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dh%29%3Dxos ἦχος], Henry George Liddell, Robert Scott, ''A Greek-English Lexicon'', on Perseus</ref>) was an [[Oread]] who resided on [[Cithaeron|Mount Cithaeron]].<ref>Aristophanes, Translated by [[Eugene O'Neill Jr.]] (1938). ''Thesmophoriazusae''. Lines 990-1000. Available at [https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0042%3Acard%3D990 perseus.tufts.edu]</ref> [[Zeus]] loved consorting with beautiful [[nymph]]s and often visited them on Earth. Eventually, Zeus's wife, [[Hera]], became suspicious, and came from [[Mount Olympus]] in an attempt to catch Zeus with the nymphs. Echo, by trying to protect Zeus (as he had ordered her to do), endured Hera's wrath, and Hera made her only able to speak the last words spoken to her. So when Echo met [[Narcissus (mythology)|Narcissus]] and fell in love with him, she was unable to tell him how she felt and was forced to watch him as he fell in love with himself.