Ironing
Ironing was the practice of smoothing out wrinkled clothing with an iron. To iron out something was to metaphorically get rid of the wrinkles, i.e. problems. (ENT: "First Flight", TNG: "Silicon Avatar")
In 2373, Kira Nerys justified her killing of Cardassians while a member of the Shakaar resistance cell to Silaran Prin, saying it didn't matter whether the Cardasssians she targeted "held a phaser in your hand or ironed shirts for a living"; as far as she was concerned, they were all legitimate targets. (DS9: "The Darkness and the Light")