iron out

verb5

1. •
   To remove (a crease or creases) with an iron.

   • That shirt still has a few more wrinkles to iron out.
2. •
   (figurative) To resolve (a dispute); to solve (a problem).

   • Let's just sit down and iron out an agreement on this issue.
   • We need to iron out the wrinkles in the plan before implementing it.
3. •
   To make (something) flat or smooth as if with an iron.
4. •
   (slang) To thrash or beat up; to overwhelm in a fight.
5. •
   (slang) To kill.