diatom

Everyday

1. A tiny one-celled living thing, a kind of algae, that lives in water and has a glassy shell made of silica. tree →
2. (science) diatoms make a large part of the oxygen we breathe and are food for many sea animals. tree →

In the lessons

In science and biology lessons diatoms appear in food chains, plankton, microscopes and oxygen; their shells pile up on the sea floor and form diatomaceous earth used in filters and toothpaste; phrases: «diatoms under the microscope», «plankton and diatoms».

Examples

• Under the microscope, the diatom looked like a tiny glass jewel. tree →
• Diatoms float in oceans, lakes and rivers. tree →
• Diatoms make oxygen using sunlight, like plants. tree →
• Small sea creatures eat diatoms. tree →
• Our class drew different diatom shapes: circles, boats and stars. tree →
• Old diatom shells pile up on the sea floor over millions of years. tree →
• Scientists study diatoms to learn how clean a river is. tree →

Note

Countable: one diatom, many diatoms. Pronounced DIE-a-tom. Too small to see without a microscope. They are not animals and not exactly plants; they are algae (protists).