See more synonyms for diddly on Thesaurus.com
noun, plural did·dlies for 2. Slang.
  1. a thing of little or no value; naught: Your excuses aren't worth diddly to me.
  2. a flaw; malfunction.

Origin of diddly

perhaps euphemistic shortening of diddlyshit
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018