1. turning into a fossil through natural processes over long periods of time
Usage: present participle of fossilise; British spelling
2. becoming rigid, outdated, or resistant to change
Usage: figurative use

Examples

• The ancient tree was slowly fossilising in the mineral-rich sediment.
• Scientists discovered bones that had been fossilising for millions of years.
• The company’s management structure was fossilising and needed reform.
• Traditional practices were fossilising while competitors embraced innovation.
• The dinosaur remains were fossilising in layers of limestone.
• His thinking was fossilising, making him resistant to new ideas.