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definitions

formatio

[fôr-mā′shē-ō]
n. pl. for•ma•ti•o•nes (-mā′shē-ō′nēz)
  1. A structure of definite shape or cellular arrangement; a formation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

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