(not) lose sleep over (something)

to not worry about something.

I don't intend to lose any sleep over this problem.

• mess with something
• mete out
• mete out something
• Mickey-Mouse
• mickey-taking
• Midas touch
• middle-aged spread
• middle ground
• middle-of-the-road
• might and main
• might as well
• might as well do something
• might is right
• Mighty oaks from little acorns grow.
• mile a minute
• mile away
• mile off
• milk of human kindness
• millstone around neck
• millstone around your neck
• mince words
• mince your words
• mind-blowing
• mind boggles
• mind boggles.