miscompute

verb

mis·​com·​pute ˌmis-kəm-ˈpyüt 

miscomputed; miscomputing

transitive + intransitive

: to make a mistake in computing : to compute wrongly

Overall, the IRS wound up sending nearly 197,000 notices recently to seniors explaining that they had miscomputed their taxable amounts of Social Security benefits …

—Neil Downing

miscomputation

ˌmis-ˌkäm-pyu̇-ˈtā-shən 

-pyü-

noun

plural miscomputations

an error caused by miscomputation

Word History

First Known Use

1637, in the meaning defined above