Smudge/smʌdʒ/ Definition 1 of 4Pro Tip 1/2Unintentional Marks Refers to marks made accidentally, often annoying and unwanted. Be careful with the pen, you might leave a smudge on the document. Pro Tip 2/2Visual Clarity A smudge usually suggests a lack of clarity or neatness on a surface. The window was covered in smudges after the rain.