A sheet of paper — usually one page — with questions, blanks, or exercises for students to fill in. Teachers hand out worksheets, students do them, and they are the everyday material of a school lesson: a grammar worksheet, a maths worksheet, a vocabulary worksheet. The idea is that the student writes on it, so it is meant to be used up, not kept like a textbook. Photocopy machines made worksheets what they are, and now many are PDFs. There is a second sense that catches learners out completely: in a spreadsheet program like Excel or Google Sheets, a worksheet is one single sheet or tab inside the file — one grid of cells. The whole file is a workbook; each tab in it is a worksheet. So if a colleague emails you asking you to "check the third worksheet," they mean a tab in a spreadsheet, not homework. Accountants have a third, related use: a working sheet where you lay out rough figures on the way to a final statement. It is also occasionally used as a verb in accounting and teaching contexts, but that is rare enough that you can safely treat it as a noun.