Direct Long Distance Dialing直拨
direct distance dialing telephone直接长途拨号电话
network direct distance dialing直接长途拨号网络
telephone direct distance dialing直接长途拨号电话
international direct distance dialing国际直接长途拨号;国际长途直拨电话
direct distance dialing netwrok直接长途拨号网络
DDD Direct Distance Dialing直接远程拨号;长途直拨
direct distance dialing DDD直接长途拨号
automatic direct distance dialing system长途直拨系统
N（名词） a service by which telephone subscribers can obtain long-distance calls by dialling direct without the aid of an operator 直接长途拨号 (British equivalent subscriber trunk dialling) [美国英语]