From Longman Dictionary of Contemporary Englishmirror imageˈmirror ˌimage noun [countable] 1 REFLECTan image of something in which the right side appears on the left, and the left side appears on the right2 SAMEOPPOSITE/REVERSEsomething that is either very similar to something else or is the complete opposite of itmirror image of The situation is a mirror image of the one Republicans faced 25 years ago.
Examples from the Corpus
mirror image• The return journey was almost a mirror image of the outward one.• The right hand half of each curve can be drawn as a mirror image.• The history that Mr Gingrich teaches is a mirror image of what the left is advancing.• Such a view is called into question by Jacques Lacan's understanding of the subject's relation to the mirror image. 