A fossil is the hard parts or marks of plants or animals that lived a long time ago. We often find them in rocks. Fossils help us learn about the past.
The scientist found a dinosaur fossil.
This fossil is millions of years old.
People sometimes call old things or people 'fossils' if they seem too old or not modern. It is often used in a joking way.
My old watch is a fossil now.
He thinks computers are for fossils.
A living fossil is a plant or animal that looks like its ancient ancestors. It has not changed much after millions of years.
The coelacanth is called a living fossil.
Some fossils live in the ocean now.
When we say something is a fossil, we mean it is very old and old-fashioned. It can no longer do its job well, usually about machines or tools.
That fossil phone does not work now.
Old fossils like that TV break easily.
Fossil fuels are types of energy sources made from old plants and animals. People use them to make power and run cars.
Cars run on fossil fuels like gasoline.
Coal is an important fossil for energy.