A nook is a small, cozy corner or tucked-away space that feels sheltered and private. Think of that corner spot in your house where two walls meet and create a perfect reading alcove, or the space under the stairs where you might build a fort. A breakfast nook is a small, comfortable area in a kitchen designed for casual meals, often with built-in benches and a table that fits snugly into the space.

Nooks feel special because they're just the right size for one or two people. They're not as hidden as secret passages, but they offer a sense of being safely enclosed while still part of the larger room. Many kids love finding nooks in their homes or schools, places where they can read, think, or simply observe what's happening around them without being in the middle of everything.

The phrase every nook and cranny means searching absolutely everywhere, including all the small, hidden spots. When you've looked in every nook and cranny for your missing library book, you've checked every possible corner and crevice, leaving no space unexplored.