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definitions

spasmus nutans

[spăz′məs nōō′tănz′]
n.
  1. Nodding spasm.
  2. Nystagmus with head-nodding movements.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.