Use 'disallow' when someone with authority denies permission to do something. Parents might disallow children from going out late.
Pro Tip 2/3
Not Just Disagree
'Disallow' is stronger than disagree; it means a clear refusal, often backed by rules or power. The committee will disallow any changes to the agreement.
Pro Tip 3/3
Expect Consequences
When authorities disallow something, there may be consequences or penalties involved. If you break the rule, the organization will disallow your participation.