Asymmetric digital subscriber line, a technology for transmitting digital information over standard telephone lines which allows high-speed transmission of signals from the telephone network to an individual subscriber, but a slower rate of transmission from the subscriber to the network.
非对称数字式用户线路，异步数字用户专线
Definition of ADSL in US English:
ADSL
abbreviationˌāˌdēˌesˈelˌeɪˌdiˌɛsˈɛl
Asymmetric (or asynchronous) digital subscriber line, a method of routing digital data on copper telephone wires, allowing high-speed Internet access and simultaneous use of the line for voice transmission.