聽筒 [听筒] (tīngtǒng) is Chinese for telephone receiver; headphone; earphone; earpiece and stethoscope. Its literal meaning is “hearing tube” – 聽 = to hear; to obey, and 筒 = tube; cylinder.
I found this word in an online Chinese dictionary I came across yesterday which looks very useful. You can search for Chinese words or characters using their characters or pinyin spelling, and the entries include traditional and simplified characters, pinyin, recordings of the pronunciation, related words, and English and French equivalents. There’s even the option of inputting characters by hand.
The dictionary seems to be part of the Chinese Tools site, which contains a translator, text-to-speech, name translators for Chinese, Japanese, Korean, Tibetan and other scripts, and other useful tools.