Keep a lid on it - Idioms by The Free Dictionary
keep a lid on (something) (redirected from keep a lid on it)
keep a lid on (something)
To keep the level of something from increasing drastically or beyond what is undesirable or dangerous. They were one of the few countries in the EU able to keep a lid on unemployment during the recession. The dictatorship has kept a tight lid on protests and public criticism of the government.
keep a (or the) lid on 1 keep an emotion or process from going out of control. 2 keep something secret. informal
keep/put a/the ˈlid on something try to make sure that people do not do something or find out about something: The government wants to keep the lid on discussion of tax reforms at the moment.