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definitions

nonsense triplet

[nŏn′sĕns′, -səns]
n.
  1. A codon that causes the premature termination of a growing polypeptide chain, thus producing incomplete protein fragments.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.