double check

from WordNet (r) 3.0 (2006)

double check
    n 1: something that checks the correctness of a previous check
         [syn: {countercheck}, {double check}]

from Moby Thesaurus II by Grady Ward, 1.0

20 Moby Thesaurus words for "double check":
      audit, balance, balance the books, check, check and doublecheck,
      check out, check over, collate, confirm, cross-check, demonstrate,
      inventory, overhaul, prove, recheck, take stock, test,
      triple-check, validate, verify