put on the line is a verb meaning "expose to a chance of loss or damage". It carries one recorded sense.
expose to a chance of loss or damage
“We risked losing a lot of money in this venture”
“Why risk your life?”
“She laid her job on the line when she told the boss that he was wrong”
Definitions, synonyms and semantic relations for put on the line come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.