1830, "pertaining to communication by sound over great distances," originally theoretical, from tele- + phonic. From 1834 in reference to the system of Sudré using musical sounds (see telephone), and with reference to Bell's invention from 1876, in which cases it can be taken as from telephone + -ic.
telephonic connection
telemeter
teleology
telepathic
telepathy
telephone
telephonic
telephony
telephoto
teleport
teleportation
teleprompter