title: Making planes plain.
abstract: The major anatomical planes (horizontal, coronal, and sagittal, including the median plane) are discussed from a historical perspective, and their correct usage is clarified. Unofficial and unnecessary terms to be avoided (for reasons explained) include midsagittal, parasagittal, and midline.
authors.affiliation: School of Medicine, University of California, Davis, USA.
authors.forename: R
authors.initials: R
authors.lastname: O'Rahilly
mesh_terms: D000715:Anatomy / Q000266:history; D049669:History, 16th Century; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D009626:Terminology as Topic