Hold/keep something in check
Definition 1 of 2
Pro Tip 1/3Context Matters
The phrase usually appears in formal or serious texts, like news or official reports. 
The central bank has increased interest rates to keep inflation in check.
Pro Tip 2/3Figurative Use
It's often used metaphorically to describe controlling non-physical things, like feelings. 
She took deep breaths to keep her anxiety in check during the interview.
Pro Tip 3/3Emotional Restraint
The phrase implies showing restraint in emotional or stressful situations. 
Despite his frustration, he kept his anger in check and calmly explained the situation.