Cell has two common meanings that come from the same root idea of a small, enclosed space:

1. A tiny room, usually one that's plain or confining. A prison cell is a small locked room where prisoners are kept. Monks and nuns sometimes live in simple cells with just a bed and desk, choosing minimal surroundings to focus on prayer and study. In a beehive, each honeycomb compartment is called a cell, where bees store honey or raise their young.
2. The basic building block that all living things are made of. Your body contains trillions of cells, each one a microscopic living unit wrapped in its own membrane, like a tiny room with walls. Some organisms, like bacteria, consist of just one cell. Others, like humans, are made of many different types: skin cells, blood cells, muscle cells, nerve cells, and more.

The word can also refer to a single unit in a battery (a battery cell) or to one compartment in a spreadsheet grid.