1. not able to be changed or modified; unchangeable

Examples

• The laws of physics are inalterable principles that govern the universe.
• His inalterable decision to move abroad surprised his family.
• The contract contained inalterable terms that could not be negotiated.
• She held an inalterable belief in the importance of education.
• The ancient monument stood as an inalterable reminder of the past.
• His inalterable routine included a morning walk every day.