fossilised

Everyday

1. Turned into a fossil: the remains or print of a plant or animal that has slowly turned to stone over millions of years. tree →
2. (figurative) Old-fashioned and unable to change, like ideas or rules stuck in the past. tree →

In the lessons

In science and history lessons it comes with dinosaurs, ammonites, ancient trees and rocks: a fossilised bone tells the reader the creature lived very long ago. Also fossilised footprints, fossilised poo (coprolite), fossilised wood. In opinion writing, fossilised ideas are ones that never change.

Examples

• We found a fossilised shell on the beach at Lyme Regis. tree →
• The museum shows a fossilised dinosaur egg. tree →
• Fossilised footprints prove that the animals walked here. tree →
• Amber can hold a fossilised insect inside it. tree →
• Over millions of years, the tree trunk fossilised into stone. tree →
• My uncle says the school rules are fossilised and need updating. tree →

Note

UK-style spelling fossilised; US fossilized. Fossilisation takes a very long time, usually thousands to millions of years, not a few years. Not every dead animal becomes a fossil; most rot away.