rootâ² canal` ther`apy. n. 1. the branch of endodontics that treats disease of the dental pulp. 2. a treatment for such disease in which the pulp is removed and replaced by filling material.
A textphone is a device that enables phone calls to be made using text. Textphone software can be used on a computer to enable it to be used as a textphone.
Headphones (or head-phones in the early days of telephony and radio) are a pair of small electronic or electric listening devices that are designed to be worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound in the user's ear.