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definitions

ac-

  1. variant of ad- before c and qu: accede; acquire.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
ac- in Medicine

ac-

pref.
  1. Variant ofad-
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.