unbreakablerule

noun

UK /ʌnˈbreɪkəbəl ruːl/

US /ʌnˈbreɪkəbəl ruːl/

A rule that can never be changed or broken.

Wearing a helmet is an unbreakablerule at our bike park.

SYNONYMS

absolute rule ironclad rule fixed rule inviolable rule strict rule

RELATED WORDS

law regulation command policy guideline

OTHER MEANINGS

2. A rule that has no exceptions for anyone.

The teacher said the no-cheating rule is an unbreakablerule.

3. A promise or agreement that must always be kept.

They made an unbreakablerule to always tell each other the truth.

4. A firm standard that cannot be bent or ignored.

Safety is an unbreakablerule in the science lab.