Definition of PA (posteroanterior)

1. Bad Bugs and Their Bites Slideshow
2. Heartburn: Foods to Eat and Avoid Slideshow
3. Understanding Multiple Sclerosis Slideshow

PA (posteroanterior): In anatomy, PA stands for posteroanterior: from back-to-front. For example, a PA X-ray of the chest is taken from back-to-front.

PA in this respect is the opposite of AP which stands for anteroposterior: from front-to-back.

Need help identifying pills and medications?
Use the pill finder tool on RxList.