基本释义:

用户长途电话拨号

网络释义

1)subscribers trunk dialling,用户长途电话拨号

2)FACD (Foreign Area Customer Dialing),长途电话用户拨号

3)Subscriber Trunk Dialing,长途电话拨号

4)direct distance dialing ,DDD,长途直接拨号电话

5)direct distance dialing (DDD),直接长途拨号电话

6)DDD (direct distance dialing),长途电话直接拨号