something that you think is true because it is very likely
the presumption that their wealth is the result of crime
On the presumption that the doctor knows best, I took the medicine.
2 [uncountable and countable] law
the act of thinking something is true, bad, or good until it is shown to not be true, bad, or good
the presumption of innocence
presumption against/in favour of
a strong presumption against development in national parks
3 [uncountable] formal
behaviour that seems rude and too confident:
She was enraged by his presumption.