keep/put a/the lid on something
put the lid on
Also, keep the lid on. Suppress, as in I don't know how but we'll have to put the lid on that rumor about her, or Let's keep the lid on our suspicions. The word lid here is used in the sense of "a cover for a container." [Early 1900s]
keep the lid on somethingor
put the lid on something
COMMON If you keep the lid on or put the lid on a situation or problem, you keep it hidden or control it to stop it becoming worse. Murray was desperately trying to keep the lid on a potential scandal. We want the public to assist us in putting a lid on crime.
keep a (or the) lid on1 keep an emotion or process from going out of control. 2 keep something secret. informal
put the (or a) lid onput a stop to. informal
1996 Observer Nothing's final. I haven't put the lid on anything.
put the (tin) lid onbe the culmination of a series of acts or events that makes things unbearable. British informal
1999 Chris Dolan Ascension Day Mum found she was pregnant a month before the wedding, then Dad put the tin lid on it by getting himself laid off.