checker

What it means

1. One who or that which checks or verifies something.

   So, keep in mind that Microsoft Word’s Spelling tool is as much a “typo” tool as a checker of spelling.

   1992, Neil J. Salkind, Applying Macintosh: Solutions, Ideas, and Tools, Macmillan Publishing Company, →ISBN, page 205

2. One who makes a check mark.

   "Essentially," said a senior vice president of the FHLBB of Dallas, "we were checkers of boxes."

   1989, M. Manfred Fabritius, William Borges, Saving the Savings and Loan

3. The clerk who tallies cost of purchases and accepts payment.

   There was a long line at the grocery store because the checker was so slow.

   1 more example

   Bud Brown said something to the checker he was supervising; she had been craning around to see what was happening. She flushed and began to run her calculator again.

   1980, Stephen King, The Mist, Viking Press

In a sentence

So, keep in mind that Microsoft Word’s Spelling tool is as much a “typo” tool as a checker of spelling.

1992, Neil J. Salkind, Applying Macintosh: Solutions, Ideas, and Tools, Macmillan Publishing Company, →ISBN, page 205

Where it comes from

From check + -er.