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definitions

mentoposterior position

[mĕn′tō-pŏ-stîr′ē-ər, -pō-]
n.
  1. A cephalic presentation of the fetus with the chin pointing to either the right or left rear quarter of the mother's pelvis.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.