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definitions

photostethoscope

[fō′tō-stĕth′ə-skōp′]
n.
  1. A device that converts sound into flashes of light, used for continuous observation of the fetal heart.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.