busy(-back) tone

• 占线音

busy(-back) tone的英文翻译是什么意思，词典释义与在线翻译：

英英释义

动词 busy:

1. keep busy with

形容词 busy:

1. actively or fully engaged or occupied

2. overcrowded or cluttered with detail

3. intrusive in a meddling or offensive manner

4. crowded with or characterized by much activity

5. (of facilities such as telephones or lavatories) unavailable for use by anyone else or indicating unavailability; (`engaged' is a British term for a busy telephone line)