on the line
US /ɑn ðə laɪn/
UK /ɑn ðə laɪn/
1.
at risk; in a position where one might lose something important
:
•
His reputation is on the line with this new project.
•
Many jobs are on the line if the company fails.
2.
on the telephone
:
•
I have Mr. Johnson on the line for you.
•
Please hold, I have another call on the line.