The English word "echo" comes from the Greek word which is also the name of a nymph: Echo (Ἠχώ). The god Zeus was notorious for his love affairs with the nymphs, and Echo distracted the goddess Hera with lengthy conversations in order to give Zeus the chance to make his escape. When Hera found out how Echo had tricked here, she put a curse on the nymph: Echo would no longer be able to speak on her own. Instead, she could only repeat the last few words of what another person said — that is, she could only echo the words she heard.
Things got worse for Echo when she fell in love with Narcissus. She was not able to communicate with him, and so she watched as Narcissus wasted away gazing at his own reflection in the water. Echo eventually lost her physical body and all that remained was... her echo!
You can read more about Echo at
Wikipedia. The painting below is
Waterhouse's Echo and Narcissus:
