hard-and-fast
Allowing no exceptions
Hard-and-fast describes rules or boundaries that are strict and inflexible, allowing no exceptions or modifications: There are no hard-and-fast rules about when to use a comma.
The term comes from nautical usage, where a ship run aground is "hard and fast"—firmly fixed and immovable.
Restored or immovable
- setArrange in position
- immutableIncapable of being changed
- unalterableIncapable of being changed
- unchangeableImpossible to modify
permanent · invariable · rigid · inflexible · unyielding · entrenched · established · frozen
Legally or morally required
- mandatoryRequired by rule
- obligatoryRequired by rule
- compulsoryRequired, not optional
- enforceableAble to be upheld
non-negotiable · ironclad · unbreakable · inviolable · strict · stringent · rigorous · absolute
fixed
Restored or immovable
- setArrange in position
- immutableIncapable of being changed
- unalterableIncapable of being changed
unchangeable · permanent · invariable · rigid · inflexible · unyielding · entrenched · established · frozen · static
binding
Legally or morally required
- mandatoryRequired by rule
- obligatoryRequired by rule
- compulsoryRequired, not optional
enforceable · non-negotiable · ironclad · unbreakable · inviolable · strict · stringent · rigorous · absolute · definitive
hard-and-fastflexible
Able to bend freely
negotiable · adjustable · elastic · discretionary · bendable
hard-and-fastopen-ended
Lacking fixed boundaries
indefinite · unspecified · vague · fuzzy · ambiguous
hard-and-fastchangeable
Capable of alteration
variable · mutable · fluid · fluctuating · unstable
hard, fast, hardly, harden, fasting, hardness, steadfast, faster, harder