An item is a single thing within a group or collection. When your teacher asks you to bring three items for the science fair, she means three separate objects: maybe a poster board, a model volcano, and a data notebook. Each one counts as an item.

The word helps us talk about things individually when they're part of a larger set. A grocery list has items on it (milk, bread, eggs). A museum collection contains thousands of items. Your backpack might hold a dozen items: books, pencils, a lunch box, and so on. Each separate object is an item.

In stores, item often refers to products for sale. “That item is out of stock” means that particular product isn't available. News reports use the word too: a news item is one story among many in a broadcast or newspaper.

People also use item to mean one point or topic in a discussion. If a principal says “the first item on today's agenda is the field trip,” she's talking about the first topic to discuss, not a physical object. In this sense, items can be ideas or tasks, not just things you can touch.